Water Chemistry, FW... hardness, pH    9/7/07
Hello to whoever answers,
<That would be me.>
I am very new to this and apologies for my unsophisticated questions. I did a test on the current water in my five gallon tank. Everything was great except for the nitrates being a bit high and the tank is due tomorrow for cleaning so that may fix that reading but the alkalinity of the water is out of sight at 300.
<Please understand that isn't "high" in a general sense. It is high relative to what soft water fish like tetras and angelfish enjoy. But it is just perfect for hard water fish such as livebearers and African lake cichlids.>
I have a water softener but do have an outside faucet that has only hardwater. I looked at ph adjusters but the instructions were very vague.
<Don't ever used water from a domestic water softener in a fish tank. It is very screwy in terms of dissolved chemicals. It IS NOT the same thing as soft water. All domestic water softeners do is replace one kind of mineral (the sort that furs up pipes) with another kind (which doesn't). As far as the fish are concerned, it's just really strange water with far too much sodium and not enough calcium salts.] Always use the unsoftened water from the drinking water tap.>
I have Chuck the Betta and four platys. They look fine but as I failed with a betta in another tank, I know that can change quickly.
<Platies will thrive in hard water. If you have "liquid rock" as we call hard water here in England, just stick with fishes that like hard water. Apart from platies, the other livebearers will do well, as will rainbowfish, gobies, glassfish, and various cichlids. Five gallons is, of course, way too small for anything other than a single Betta. It is absolutely not acceptable for platies, which need at least 10 gallons. They are active, social fish than need swimming room. The males are also somewhat aggressive, so having some swimming space helps here, too.>
My questions are how much ph reducer is safe to get the ph down to 120?
<Please don't. Until you completely understand how water chemistry works, don't try and change it. Since pH isn't measured on any scale that includes 120, you clearly don't understand how water chemistry works yet. So leave well enough alone. Buy fish that like hard, alkaline water. Use the unsoftened water. Do frequent water changes. That's plenty enough to master just now.>
Is the hardwater preferable?
<99 times out 100, yes, it's better to buy fish that match your ambient water conditions. They will be healthier and breed more readily. Moreover, you can do big, regular water changes (50% weekly is ideal) without worrying about changes in water chemistry or the expense of softening water.>
Is this a reason for the sudden mess of algae?
<No.>
I also need to warm the water but is there any heater safe for such a small tank?
<You don't have a heater yet? Go, now, buy one.>
I got one with the tank and it is a 25 watt Slim-Tech.
<Sounds fine.>
Thank you very much,
<You're welcome>
Linda
<Neale>

Water Chemistry II... pH   9/7/07
Thanks Neale,
<Hello Linda,>
I got the PH reducer number of 120 off the test strip bottle.....Quick Dip.
<Does not compute... does not compute... The pH scale runs from 0 to 14. There's no 120. I suspect you are reading something else by mistake, perhaps general or carbonate hardness (both of which could be 120 mg/l).>
I have done book and internet research but everyone seems to have answers that vary just enough that I get more confused than informed. I am glad I found WWM. I promise not to become a permanent feature.
<Hah!>
I do have to throw in how disappointing it is how little correct information comes from the places where you get these poor fish.
<Indeed. But you have to remember the motives. Pet stores want you to keep coming back to buy stuff. They want you to have just enough success to stay interested. But they have no vested interest in your fish staying healthy provided you keep buying more fish from them. People like us here at WWM don't get paid for what we're doing, we do it because we want you to enjoy your hobby and your fish to stay healthy. Who you gonna trust?>
I will switch to the untreated source of water and test it to see what it is like too.
<Good.>
Will the platies do ok until next month when I am rich again and can get a larger tank?
<Yes.>
And cycle a new tank. I have the 5 gallon tank on a regular sturdy table. Will a ten gallon tank need more support?
<Quote possibly. Depends on the table of course. If it's strong and well built, could be fine. If it's a rickety thing, then don't bank on it. I have a 10 gallon tank on a cheap chipboard TV stand thing, and that works fine. So there are plenty of budget options out there. Just buy something designed to support serious weight. TVs are heavy, hence the TV stand was a good choice.>
Are four platies too many for ten gallons?
<Four will be fine in there, you could probably keep twice that many without problems, provided you kept on top of water changes and didn't overfeed them.>
Is the 25 watt heater sufficient for ten gallons?
<Depends on your air temperature. If your home is centrally heated and never gets that cold, should be fine. If the tank is in an unheated room, might not be so effective. But my guess is you'll be fine.>
Sorry I wasn't using it but I was afraid of "cooking" the poor things.
<That's what a thermometer is for. Get a cheap sticky LCD one (costs about $1) and stick it on the tank.>
I need to move their tank as it is too close to a door and in the winter may be too drafty.
<Quite possibly.>
When I clean the tank today, I am going to clean the algae off their rocks and plants with a new toothbrush and just plain water. Is that ok?
<Leave the algae: your platies will be eating it, and it's very good for them. They are vegetarians in the wild, and 50% of their diet in aquaria should be algae-based, either algae itself or "livebearer" flake food that is made from algae. The only place algae needs to be removed is the front glass. I leave it everywhere else, because it looks nice and the fish like it. Also, I don't like creating work for myself.>
I have read that turning their light on less will help with regrowth.
<No, doesn't work that way. Instead of green algae, which the platies eat, you end up with low-light diatoms, which platies don't eat. Algae is harmless. Sit back, and learn to ignore it. I'm sure you have lots of other projects you could be doing. Scraping off algae is not one of them.>
I have seen Magnets for sale for algae and have no idea if that is workable. Anything else I can do?
<I use a plastic fuzzy kitchen scourer thing for cleaning algae. Cheap and cheerful.>
When I prepare the new tank, is it better to use bottle bacterial preparations or water from the current tank?
<Take some of the filter media from the old tank (30-50%) and stick into the new tank. Much better than bottles, and a million times better than water.>
How will I know when the bacteria is where it is supposed to be?
<Do what I say above, and it's a sure thing.>
I knew nothing about cycling with the five gallon tank and was lucky all of them survived and want to make a move better for them this time.
<Very good.>
I really enjoy my fish and intend to get better at this. My fish and I thank you for improving their world.
Linda
<Glad to help. Enjoy your hobby. Neale>

Suggested "buddies" / high ph issue – 09/01/07
I've set up our first tank and am a true novice. The 20-gal tank is about 3+ weeks old and holds at 78 degrees F. Artificial plants are moderately included and a cave is available for cover. We've chosen to filter the water via a power filter. We started with 2 platy's and 1 swordtail (male).
Two died (I think they came from the same stock already sick) and we have 1 remaining platy (unknown gender, but getting fat and is a pig!). We added a dwarf Gourami (male), and both fish look very healthy and have good appetites. Despite the characteristic nips by the Gourami, platy seems to be fairing well.
<Ok.>
I've performed weekly 10% water changes and gravel vacuuming to help establish a balanced aquarium and to care for our remaining two fish. I've occasionally treated with Ammo Lock as needed, added a bacteria supplement, etc. Here's the problem: our tank as at a consistent ph of 7.7ish.
Diligent - but gradual - treatment with a ph reducer has done little to nothing in changing the overall ph. I tested ph of our tap water and it starts at about 8.0.
<10% water changes aren't really worthwhile. They're better than nothing, obviously, but 25-50% is better still, and not really any extra effort. I'd skip the pH buffer; bit of a waste of time if you're not softening the water as well, and the scope for disaster if you make a mistake is considerable.>
We wanted to add more critters, but have several questions before doing so:
1. What fish would best work given our higher ph?
<Don't focus on pH, it's a red herring. Concentrate on hardness, because that's what your fish care about. Newbie fishkeepers tend to fixate on pH because it's a simple number and easy to understand (6 = acid, 7 = neutral, 8 = alkaline). But fish themselves don't "feel" pH in any real sense. What matters is how much mineral content is in the water, and how that effects things like osmoregulation and pH stability (which they do care about). In hard water aquaria, which generally have alkaline/basic pH levels (7.5-8) your best bets are rainbowfish, livebearers, and gobies. All these fish tend to adore hard water. Tetras, Corydoras catfish, gouramis and so on will usually adapt just fine, but it's sub-optimal for them, and in some cases may reduce their hardiness, longevity, or breedability. Have a look at my article on just this topic, here: http://www.wetwebmedia.com/FWSubWebIndex/fwhardness.htm .>
2. We wanted to preferably add 2 female dwarf gouramis (to calm the nippy male), another platy, and one dwarf African frog. I've waded through many questions on your site, but can't seem to find info as to whether these are all compatible. I did learn that dwarf gouramis like soft, acidic water, which is not what we have. Lani, our current dwarf gourami appears happy and healthy, though, so I'm tempted to add more anyway. Suggestions?
<I'm personally not a fan of either Dwarf gouramis (plagued with disease) or African frogs (don't tend to last long in fish tanks). With regard to the Dwarf gouramis, read through the reams and reams of messages here about sick specimens of this species. If you have one healthy specimen, count yourself lucky and enjoy. The odds of you getting three specimens, all healthy, are, to be honest, nil. Unless you're getting them locally bred, of course.>
3. Finally, my daughter wanted snails but I've vetoed that after reading info on your site. What bottom feeders would you suggest for algae control given our tank size / conditions?
<Nothing wrong with snails. It all depends on which snail you get. Nerite snails don't breed in aquaria and don't eat plants. They are colourful, weirdly shaped, and stay small (about 1 cm across). Pond snails, on the other hand, can breed rapidly and will eat plants. Apple snails sometimes eat plants, but are also sensitive to water quality and nippy fish, and often die in fish tanks despite being quite hardy when kept in their own quarters. So, it's a question of finding out what snails are available, and acting accordingly. Otherwise, I think Cherry shrimps are the benthic algae-eater of choice at the moment. They are basically hardy (though will be killed by many medications) and very pretty. They also breed quite readily, though not explosively, and being fairly short lived (around a year?) what you end up with is a stable colony. The other nice little bottom dweller is the Kuhli loach. It's a sociable, shy little beast, but 100% harmless and rather adorable with its orange and brown colouration. It isn't wild about hard water, but adapts fine. A good hard water alternative is the utterly cute Rhinogobius duospilus (also known as dragon/white-cheeked goby). It's a master of colour changes and very outgoing, staying firmly in view at all times. At about 3.5-4 cm when mature, it would be ideal for your aquarium kept in a small group with lots of caves for hiding places. It won't eat flake, but on (wet) frozen bloodworms and brine shrimps its easy to keep.>
Thanks in advance for your thoughts and opinions.
Kristi
<Hope this helps, Neale>

Re: Suggested "buddies" / high ph issue... Chloramine issue in tap water  9/2/07
Neale,
Wow - you are a genius!
<Blush.>
I tested as directed for a possible chloramine issue in the "new" dechlorinated water. Gosh by golly - you were right!!!!
While the ammonia levels in the tank this morning were nil, the dechlorinated test water registered .5 ppm. I can see how this can shock more fragile fish during a large water change. Luckily the molly and dwarf gourami seem to have bounced back - whoosh!
<Yes, they should do. Ammonia kills primarily through long-term exposure, and within reason fish can repair slight damage and bounce back should the situation improve quickly.>
So now we know that my water conditioner is not chloramine-safe. Now what?
Do I need to purchase another type of water conditioner, and if so will it specifically say that it *is* chloramine-safe? Or can I add Ammo-lock to the "new" water right before adding it to the tank?
<I've never used Ammo-Lock so can't comment from experience, but the marketing blurb I read online seems to indicate it should work just like a regular dechlorinator: add to the water, stir, wait a few minutes, and then pour it into the tank.>
Also, would the spike in ammonia given the 30% water change explain the fact that the nitrite level didn't decrease from pre water-change values? I assume the ammonia released in the water change has already converted to nitrites, hence the 0 ammonia reading in the tank today and the continued nitrite level of 2.0 (same reading as the "old" water).
<Sounds plausible. Over the course of the week, you should see ammonia and nitrite drop to zero. Quite likely within a day or so. If not, the problem might be something else.>
In terms of nitrite levels, I know it is concerning to have anything above 0. Most guidance I can find, however, refers to tanks that have already been cycled. Mine is in the process. I plan on keeping with the weekly water changes, but what is the max nitrite level that would necessitate an emergency water change?
<Max safe nitrite is 0; everything above that does increasing amounts of damage to your fish. The lethal level of nitrite is about 1 mg/l, and you should be aiming for no more than 0.5 mg/l, and ideally less than 0.2 mg/l during the cycling stage.>
On another note, thanks for the glassfish (unpainted) suggestions and article on the site. It was this info that suggested they would be a good addition to my hard water / high ph tank. The school of five (collectively named "Ian") are quickly becoming my favorite. They are munching up the frozen blood worms quite nicely, and nibbling on flake. I find that I have to work at getting bloodworms to the ADF before "Ian" and my gourami steal them. It's quite funny.
<Glassfish are cool. They have funny faces. When I sit in front of the tank, they slide up to the front and stare down their pointy noses at me. Right now, they sitting at the corner of the tank next to my work table, begging for food. The big glassfish species (some get around 20 cm/8") are really impressive animals, and would be a lot of fun to keep. Mine also seem to be rather bullying amongst themselves, and watching them chase each other is always entertaining. It's a shame over the years these hardy, long-lived fish have been so mistreated through tattooing and dyeing. They may not be the most colourful fish on Earth, but they have their own natural charm that makes them well worth keeping.>
Thanks again for your guidance!!!!! I'm sure we would be having several
fish funerals without you all!
<Not a problem, and we're happy to help.>
Take care,
Kristi
<Cheers, Neale>

Re: HELP!! ph shock?   9/2/07
Neale,
<Kristi,>
Thanks for your reply. After doing more research on your site (loooooooove it b/t/w), we added critters tolerant of higher ph conditions just yesterday. That included five 5 glassfish, one molly and 1 ADF.
<I'm a great fan of glassfish, and you'll enjoy them. The only downside to glassfish is they won't eat flake or dried foods, only live and (wet) frozen foods (live brine shrimps and daphnia, plus frozen bloodworms makes a good staple). Seafood from the grocery store will be taken, too. I feed mine on bite-size chunks of prawn and mussel, for example. They ADORE lobster eggs, which you can buy frozen from any decent marine aquarium store. Glassfish are quite intelligent, and will soon learn to beg for food and try out anything you throw into the aquarium.>
Except for the molly (shy, eats little, hangs out in top corner alone), they all seemed to be settling in fine. I was due for a weekly 10% water change and your reply gave me confidence to do about a 30% change instead. Increasing Nitrite levels - along with adding the new fish in a relatively young tank (just under 4 weeks old) - also went into my reasoning.
<Assuming pH and hardness of the "new" water coming in is similar to the pH and hardness of the "old" water going out, you can do as big a water change as you want. Some aquarists will do 90% water changes! Truly, the bigger the better. But, if the pH and hardness of the new water is different to the old water, the fish may be shocked or stressed for a period of time related to how great those differences were. Most fish will come round in a few hours unless the changes were so dramatic they proved fatal.>
It's not two hours later and my gourami and molly seem to be shocked (rapid gill and fin movement...both resting on the bottom). The ADF, platy and glassfish all appear fine and normal.
<No real surprises here. Mollies simply aren't hardy in freshwater tanks, which is why I ALWAYS tell people to keep them in brackish water. In my opinion, mollies in freshwater tanks are not suitable for beginners. Gouramis were hardy once, but dwarf gouramis especially are so in-bred and so plagued with bacterial and viral diseases that I've written them off a "bad lot" and simply won't recommend anyone keep them, period. Platies seem to be generally robust, though this varies, but glassfish are wild-caught and provided they're not dyed/tattooed, are very hardy animals. Anyway, just let the fish acclimate to the new conditions, and I'm sure everything will be fine.>
The ph of the tap water runs what the tank is (about 7.7) and it was treated with water conditioner. So I don't think it was ph shock. Water temp is the same. I'm trying to figure out what shocked the fish so much. I use a 2 1/2 gallon bucket and filled it up three times to replace water taken from my 20 gal tank during vacuuming (hence the ~30% change).
<All sounds fine. It may be unrelated, and its only because you were working on the aquarium that you noticed two of the fish were acting strangely.>
The water conditioner used for the 7 1/2 gallons was added entirely to the first bucket only. I was thinking the dose would also treat the following two buckets when they were subsequently added to the tank. Was this a disastrous mistake?
<Water conditioner is usually fairly innocuous stuff, so short-term overdoses shouldn't cause any problems for most fish, especially if you corrected the situation a few minutes later. If this truly was the problem, I'd expect all the fish to show signs of distress, not just two of them. So for now, I'd not worry about the water, but concentrate on other potential problems. Mollies react badly to low pH/hardness and high nitrates for example, so check those. They also prefer salty water (which, luckily, is acceptable to glassfish and platies too, though not gouramis and frogs). Dwarf gouramis are just not reliable fish, and frankly I have no faith in them at all.>
Ugh - I'm sick about my fish not feeling right.
<I sympathise.>
Something happened related to this water change - if only I knew what.
<Simply because two things happened at the same time doesn't mean they're connected. Assuming the new and old water had fairly similar water chemistry and temperature, and you added sufficient dechlorinator, then you shouldn't be concerned about water changes. Consider other factors! Do also check your water supply doesn't contain chloramine. Many water boards use this to sterilise the water. While harmless to us, it is very toxic to fish, and NOT ALL dechlorinators will remove it. Often, all they do is remove the chlorine part of chloramine, releasing toxic ammonia into the water. Mollies and dwarf gouramis are likely to be very sensitive to this, so if you have an ammonia test kit, make up a new batch of fresh water, add dechlorinator, stir, and then take a reading. If your dechlorinator is not chloramine-safe, then that might be your problem.>
Any immediate actions I can take to help my fish feel better? Help!!!!
<Not really; let them relax quietly and recover. Increase oxygenation if you can by checking the filter is circulating the water nicely and creating some splashing at the top.>
Thanks!
Kristi
<You're welcome, Neale>

Coral Chips use in FW for alk.   8/23/07
Hi Crew / Mich,
<Alan, Bob with you this time>
Will coral chips helps to buffer up in my fresh water aquarium? I heard a lot of hobbyists are doing that to maintain the neutral Ph, does it help or is it a myth? Thks. in advance.
Cheers.
Alan
<These sources of calcium carbonate do/will indeed provide alkalinity, reserve. Bob Fenner>

Re: Coral Chips use in FW for alk.   8/24/07
Dear Crew,
<Alan>
Thks. for the prompt reply. Further to my questions on coral chips, what
is the amount to be used in terms of weight?
<Best to experiment here... try a few ounces... in a net-like bag (perhaps a Dacron one sold for this purpose in the pet-fish interest), rinsed (to remove dust) and placed in your circulation/filter flow path... test the water every few days... for pH, alkalinity>
Will over usage of coral chips caused Ph readings to go beyond 8?
<Mmm, doubtful... not "that" soluble in most freshwaters...>
Thks. in advance.
Alan
<Welcome. BobF>

Re: Coral Chips  8/27/08
Dear Crew,
Hope I'm not a nuisance to you guys. I have one last questions. If my pH reads 6, am I right to say that the coral chips are more soluble?
<They will be more soluble in lower pH water, yes. BobF>
Thks. in advance.
Alan

Re: What's going on? FW quality  8/7/07
Hi Neale,
<Hello Scott,>
Thanks for the quick response, and sorry to bug you again, but...
<It's fine...>
I agree that the KH and GH is too low, but do not know how to raise them without adverse effects. Referring to the KH I use to use a phosphate buffer to control PH and it worked well but also caused hair algae, so I went to just baking soda, but if I add enough to raise the KH to the level you suggest then the PH raises to 8.0 and I prefer to keep soft/acid type fishes. (Discus on the way to go with the blue ram, Cory's and pleco's.
Silver dollars will go to the other tank.) Even the 7.2 is IMO too high and I would like to keep it lower at between 6.5-7.0. Any ideas there?
<I personally always recommend against keeping fish in acidic water conditions unless you have to, e.g., for breeding purposes. There's no real advantage. Let's look at why. First of all, pH is a mirage. Fish don't "feel" pH. They only feel the total dissolved solids, since that's the only aspect that impacts their biology (specifically, osmoregulation). Adjusting pH up or down without first figuring out the correct General Hardness and Carbonate Hardness is like painting your motor car black and saying that turns it into a London taxi cab. So, forget about pH, and forget about buffers. Fish will adapt to a range of pH and hardness values, and silver dollars for example are fine in slightly alkaline, moderately hard water. The advantages to keeping them thus are two-fold. Firstly, water with appreciable levels of hardness (especially carbonate hardness) resist water chemistry changes. Secondly, the filter bacteria prefer alkaline/hard water conditions and hate soft/acid water conditions, so you get better water quality. Finally, all fish prosper best where the aquarist can do large, regular water changes. Most fish would sooner be kept at sub-optimal water chemistry values provided those values were constant (as they would be with regular water changes). Keeping fish are "optimal" values if soft and acidic won't help if the pH changes between each water change, as would happen if the water changes were small and the aquarist had provided no reliable buffering capacity to the aquarium.>
The GH issue is that I use RO Right to reclaim the RO water and although the amount added does not give me a reasonable GH reading, it does give me a TDS reading of about 110ppm all by itself.
<Any reason you don't mix RO water with plain tap water? I mix rainwater with tap water to get soft, slightly acidic water when required and it works perfectly. I use the ratio 25% tap water to 75% rainwater. You can use a Pearson Square to figure out the GH or KH of the water you produce by this method. Even a 50:50 mix should get something with moderate hardness and a neutral to slightly alkaline pH ideal for silver dollars, Corydoras, etc. The reason I say mix with tap water is its a cheap approach that combines the ease of large scale water changes with the buffering capacity present in many local tap water supplies. My tap water here has something like 20 degrees dH and a pH around 8.>
I have heard that this is a good product, but I too would have expected its makeup to provide more calcium and magnesium or what ever the test kit tests for. Another possibility is that the test kit is faulty, but I have already tried 2 different test kits and have the same readings on each.
<Probably is a good product, but fundamentally fiddling about with buffering solutions is hard work. Certainly, you should "practise" on disposable buckets of water to get the exact water chemistry you want before keeping any fish in it. I repeat, what matters with freshwater fish is *consistency* in the water chemistry, not what the actual values are. Within reason, fish will adapt to a spectrum of pH and hardness values.>
As for the cloudiness I did try a water clarifier but that did not work. In fact it worsened the problem temporarily.
<Odd. One thought might be a diatom bloom. This normally only happens in marine tanks, and the solution is a UV filter. I'd still tend to opt for breaking down the tank, cleaning, and returning the fish to the tank once cleaned. See if the problem happens again. I call this the nuclear option -- a bit like instead of faffing about with a computer trying to figure out the problem, you just erase the hard drive and put everything back. In the long run, a time saver.>
I will have to try the vegetables, because the silver dollars hunt out the algae wafers even in total darkness. I know this because I have a night vision camera that I watched with after dropping a wafer into the tank in total darkness, and within 5 minutes or so the silver dollars will slowly zero in on the wafers by smell or what ever sense they have, and eat them.
(can fish see infrared light? It sure made their eyes glow brightly).
<No, fish can't see IR, though they don't need to. Their eyes are much more sensitive to visible light than ours, and some can also see UV to some degree. They also have a very good taste/smell sense plus the lateral line system for "touching" at a distance.>
Hopefully they will not smell cucumber or if they do will not be interested in it. I have never fed them such so they may not recognize the smell as food and therefore leave it alone.
<Worth a shot. You can't overdose vegetables because they contain so little protein. So sticking half a head of lettuce in a fish tank won't cause anything like the ammonia pollution of a one extra pinch of flake. I often leave big chunks of vegetables in my tanks for days at a time. The softer they become, the more the fish like them.>
How do pleco's get their protein?
<From vegetables and algae. Because there's so little protein in 1 gramme of vegetable compared to 1 gramme of meat, plecs need to forage more or less constantly, and will usually zoom right in on a meaty treat like a mussel given the chance. A few plecs, notably the genus Panaque, can actually extract proteins from digesting wood something very few animals can do.>
Thanks again,
Scott
<Good luck, Neale>

ph keeps dropping, FW, simple reading, sodium bicarb. addn.   8/4/07
Hi crew
I have tried hunting my problem down on your website but I am not if I am comparing apples with apples or not. So forgive me if this is doubling up.
We have two tanks, one is around 54 litres, the other just over 60 litres (New Zealand here so don't know gallons sorry).
<A little less than four to a gallon...>
Both are freshwater tropicals, community tanks - tank one has a beta, a sword tail and three "adult" Plecos about 4 inches long each,
<Wonder what species>
while tank two has 6 neon tetras and 20 3 month old Pleco about 3cm long!
<Wow, tiny>
We were not expecting babies!!
Both tanks have internal filters - Shark and similar, under floor gravel trays and those vertical tubes with an airstone inside connected to an air pump. We feed every second day, flakes for the top feeding, and pellets for the Plecos, once a week or so they get peas, dried tube worms, courgette etc. That's the history NOW the problem.....we continuously have issues with our pH dropping down to 6 or less, whilst desperately trying to have it sit around the ideal 7 - 7.5.
<Mmm, a lack of alkaline reserve is all...>
Both tanks have live plants in them, however tank one had new plant introduced two weeks ago which has died already.
<Likely a related issue with the pH fluctuation, lack of alkalinity>
We do probably 1/3 water changes every week or two (depending on how busy) and when we do so we test the pH in the buckets first, add Stresscoat etc and away we go. I have tried adding pH stabilizing blocks, but again this morning both tanks have dropped again, and it has only been a week since last water change. What are we missing here? All advice greatly appreciated.
<Mmm... a read: http://wetwebmedia.com/FWSubWebIndex/fwph,alk.htm
and the linked files above, and likely just the blending in of a bit of baking soda with your change water ought to do it here. Cheers, Bob Fenner>

High pH but soft water
Hi Crew,
<Ave.
I've been reading through your FAQ pages on water chemistry and have found a lot of info so far - thanks for all your efforts! I had an additional question or three (or four) that I didn't see the answer to.
<OK.>
A little background: we have two 55-gallon freshwater tanks. One holds a single full-size Oscar, and the other is a community tank with cherry barbs, gold barbs, platys, neon tetras, Cory cats, and several healthy live plants and some real wood mixed in with the plastic plants. Oh, the Oscar tank also has a large piece of real wood. Both receive excellent filtration (Fluval canister filters as well as HOB filters), steady heat, regular maintenance, and weekly partial water changes. Ammonia and nitrite = 0, nitrates < 10 ppm.
<All sounds fine.>
So... Our water has a pH in the range of 8.4 - 8.8 right out of the tap - I read elsewhere the FAQs that apparently the water in Massachusetts is purposely adjusted this way to protect the pipes. However, the water also happens to be very soft - only about 1 dGH and 2-3 dKH. This high pH, soft water is a less-than-usual combo as I understand it, but not impossible to get. Perhaps the city is also adding a softener to the water.
<High pH and low hardness can come about in multiple ways. Sometimes its an artifact of the test kit being used: if your water has a high permanent hardness (chlorides etc.) but a low temporary hardness (carbonates etc.) a General Hardness (dH) test kit will register "high" hardness but a Carbonate Hardness (KH) kit will register a "low" hardness. Soft water with high levels of ammonia can also register a high pH, because ammonia raises pH even though it doesn't make water hard. Domestic water softeners also mess around with water chemistry in ways producing something not really suitable for fishkeeping. In any event, the water you have isn't acceptable. At the very least, I'd be added a carbonate substrate to the aquarium and/or adding "Malawi" salts to the water to raise the KH so that the water will be much better buffered than it is now. I'd then be selecting hard water fishes such as livebearers or Tanganyikans or rainbowfish that will thrive in the resulting water conditions. By doing this, the mechanics becomes a no-brainer and I can forget about water chemistry.>
Anyway, Question #1: My first main question is about the softness of the water. I understand about low KH and the risks of rapidly dropping pH if there is no buffering capacity in the water. But is there anything INHERENTLY harmful to fish about very soft water with low GH? If soft water is bad for other reasons, what are those reasons? And is it worse to have low GH or low KH?
<Not if the fish have adapted to it. Don't expect the fish to breed readily, but who knows?>
I'm asking because in both our tanks, the water ends up being about 7.4 - 7.7, and I have tested the pH regularly and have never observed a crash or even a significant change in it from week to week, even with all the wood in the tanks.
<Indeed, the wood is acidifying the water, and if you're going from pH 8-point something to 7.4 between water changes, that's really not good. Raising the ambient KH should prevent this.>
So either my test strips showing low hardness/alkalinity are wrong (although they're new), or the system is simply stable enough week-to-week by itself to hold its pH steady.
<Large water changes "temporally buffer" chemistry changes by diluting them. Whether you consider this stable or not depends on your point of view.>
However, we have had some untimely demises in our community tank, and I'm wondering if it's because the low GH of the water.
<Probably a factor, yes.>
I really can't think of anything else, since as I mentioned before, all the other water chemistry parameters are pretty good except for this low GH/KH thing. If the softness of the water is not inherently harmful, then I'd rather not mess with it by adding buffers, for fear of raising the already-kind-of-high pH, you know?
<Raising pH/KH hardness is usually easy. Add coral sand to the tank, and then a reduced dose of Lake Malawi salts to each water change. Experiment to see how much of these salts you need each time. But since high KH water is inherently chemically stable, once you've cross this bridge, it's pretty much idiot-proof. Going brackish water, i.e., adding marine salt mix, does the same thing, and in this case you could keep salt-tolerant things like mollies, guppies, gobies, etc. as well as standard brackish water fare.>
However, if soft water damages the fish in some way, then I'll gladly add something to
change it. What do you think? (The one thing I have read about soft water is that some fish are more likely to breed at certain hardness levels, but we're not breeding fish right now so that's not really a concern.)
<Soft water only "harms" fishes that need high levels of hardness (livebearers, goldfish, etc.) But soft water is also like balancing spinning plates on a pole, you have to keep testing and adjusting stuff all the time. Fish hate rapid changes in pH and hardness far more that they dislike being stuck at something suboptimal on a permanent basis. For example, you can have a tank of cardinal tetras in hard (20dH) alkaline (pH 8) water for years and they'll be fine. But suddenly reduce the hardness to the optimal values for breeding (~2-3dH, pH 6) and they'll die even though those conditions are "better". In fishkeeping, focusing on stability is always better than focusing on the numbers.>
Question #2: Regarding the pH range that I mentioned, most of the advice from the WWM crew that I've read on other pages here seems to strongly lean toward leaving it alone rather than trying to add pH adjusters to bring it down. It seems like it's on the high side, but not too terrible, and fish should be able to adjust to it. Is this also your recommendation for me?
<Up to a point, yes. Because you have a very low KH, I just don't think your tank will be stable in the long term. I've seen pH crashes in tanks too often to be comfortable recommending this as a way forward. It's do-able, but it isn't easy or reliable.>
Question #3: More broadly, I have a question about using something like pH Down in the first place. It seems to me that the whole point of having an alkaline buffer in your water is to prevent shifts in pH, right?
<Well, "point" is perhaps not the right word. Water with high carbonate hardness has a high (= basic rather than acidic) pH, i.e., something over 7. The problem is in common speech we treat "alkalinity" and "high pH" as synonyms, which they're not.>
So oftentimes you hear about somebody adding pH Down (which I think is basically just acid) to their tank and it doesn't do anything, because the acid is just being buffered.
<Correct. It's almost always a waste of time and money unless you've softened the water. Acid buffers are useful when you have a soft water aquarium (say, around 5 dH) and the acid buffer stops the water pH dropping below, say, pH 6.>
So, if someone adds enough pH Down to finally "overcome" the buffer and actually change the pH, won't they be exposing the tank to further, more rapid shifts in pH, because now the buffer's been all used up?
<Yes. This is buffering capacity. Roughly speaking, water at 6 KH has twice the ability to neutralise acid as water at 3 KH.>
Wouldn't this kind of defeat the whole purpose of having a buffer to begin with?
<Buffers work both ways. You can have buffers that fix the pH at acidic values or neutral values as well as basic values. So it depends on what you're after. If you're keeping Malawi cichlids, a buffer that "fixes" the tank at pH 8 is ideal, but if you're breeding Apistogramma, you want something that fixes the tank at pH 6. It's horses for courses.>
Not to mention the fact that by adding all these chemicals, the osmotic pressure in the tank has now been raised way up and stress has been put on the fish that wouldn't normally have been there? So correct me if any of this is wrong, but if that's the case then it seems like using something like pH Down should be done only in an emergency. Thoughts?
<Water chemistry changes SHOULD NEVER be done in response to an emergency. Water chemistry changes are something you do slowly and deliberately to create conditions for certain things, like breeding fish. Otherwise water chemistry STABILITY is what matters.>
Okay, one more. Question #4: Now, if you do think that some kind of buffer is warranted for my tanks to raise the hardness of the water (my first thought would be crushed coral in the canister filter), it seems all but certain that it will also raise the pH, correct? I'm afraid that since the pH already high, adding something this could do more harm than good. It would require using pH Down or something - and see my above questions about concerns over that.
<Coral sand is a buffering agent, because it adds calcium carbonate (among other things) to the water. You can add 5 tonnes of the stuff to the aquarium and the pH will only rise to around 8 and then stop. Buffers *resist changes in both directions*, they don't force changes constantly upwards (or downwards). This is why the pH in a Lake Malawi aquarium is steady: the KH in the water is actually fixing it and stopping it from either going up or down. In your case, creating a tank with a high KH and a pH around 8 would be great, because you'd have a beautifully stable aquarium in which you could keep all sorts of hard water fishes. Have a read of this: http://www.wetwebmedia.com/FWSubWebIndex/fwhardness.htm and then this: http://www.wetwebmedia.com/FWSubWebIndex/fwh2oquality.htm .>
This is a lot to be asking at once, I know, but I've seen that you folks prefer it when people ask all the related questions they have in a single email. So, there it is. Any info you have would be greatly appreciated. Thanks so much and talk to you soon.
- Chris
<Hope this helps. Good luck! Neale>

High pH and Hard Water – 07/18/07
Dear WWM crew,
The information I have been reading from the site is really very helpful.
<Cool.>
I have 38 gallon freshwater tank, only 3.5 months old, with10 mollies (about 1" long) and 150 fries, 12 plants and 2 driftwoods in it. Recently I tested my water and found the PH is far too high, about 8.7
<That's quite high, but should be within the range for Mollies. Since yours are breeding like rabbits, you obviously must be doing something right.>
I read lots of information and realized top-off water may have caused the PH to increase as our water is very hard. (Our tap water: close to PH 8.0 / alkalinity 300 ppm)
<pH 8.0 and alkalinity 300 ppm is close to paradise for Mollies. Add some marine salt mix (around 6 grammes per litre) and your Mollies will wet their underpants with joy.>
Test results:
Nitrate: 40 ppm (Kind of high)
Nitrite: 0 ppm
Ammonia: 0 ppm
Total hardness: 250 ppm
Total alkalinity: above 300 ppm
PH: 8.7
(I added Seachem Life Bearer Salt to the tank water.)
<Life Bearer Salt is expensive for what it is. Just use plain vanilla marine salt mix, which you can buy in nice big boxes and tubs to get the most economy.>
I would like to lower PH to 7.6~8.0 safely and try to avoid using chemicals if possible. I am setting up an RO/DI unit. However, I do not know what the correct way is to use RO water to correct the situation here. Hope your great knowledge and opinions can help me.
<Adding RO water will reduce the pH and hardness. But just so we're clear here, RO water isn't the same as softened water from a domestic water softener (a lot of folks get the two confused). You'll need to do some trial and error to see what works, but as a first-pass, mix 25% RO to 75% tap water and see what you get. All this said, unless your Mollies are clearly unhappy, I wouldn't be overly concerned about it. I'm a bit confused about why your aquarium has such a high pH though. If you're doing 50% water changes each week, and your tap water has pH 8.0 when fresh, then I'd expect the pH in the tank to be around 8.0. Driftwood sometimes lowers the water pH. I can't for the life of me understand why the pH would go up so high. Let's cross off one possibility though -- you *are* using a dechlorinator that removes chloramine as well? If you're in an area where chloramine is used to treat water, failure to do so leads to ammonia in the water, and this raises the pH.>
I know this correction should be carried out gradually. A few questions I couldn't find answers on this site, as most information on RO unit seems to be about Marine tank.
<pH and hardness changes should be done gradually, yes, but Mollies are true euryhaline fish meaning they adapt almost instantly. So do a 25% water change one day and then another 25% water change the next and you'll be fine. I've adapted Mollies between seawater and freshwater *within an hour*.>
* Do I need to add anything to RO water before pouring in the tank?
(For top-offs, it is okay to use directly in the tank. Am I right? What about water changes?)
<RO should be safe. Tap water should be treated.>
* Water change using RO water - What's the safest amount I should try each time?
<Never ever add RO water straight to the aquarium *except* when making good small losses from evaporation. Mix the RO water with the tap water, and add *that* to the tank. I personally like to do 10-15% water changes every day or two on some tanks, but other times as much as 50% a week. There's really no maximum amount provided the water going into the tank has roughly the same pH and hardness of the water taken out.>
* What's the ideal alkalinity I should try to achieve?
<For Mollies, the harder the better. They don't care.>
Anything else I should be aware about using RO/DI water to reduce the alkalinity and PH?
<Not that I can think of. Just mix it with tap water first, and test the result to see it's something good for mollies. Around pH 8, 20 dH, SG 1.003-1.005 is just about perfect for them.>
Thanks a lot for your help in advance!
Kathy
<Good luck, Neale>

Re:  High PH and Hard Water – 07/18/07
Dear Neale,
<Hello Kathy,>
Thanks so much for your very detailed reply. I understand why you are confused about my tank water PH going up so high if my tap water PH is only 8.0. In May I went back to Taiwan visiting my family and found an aquarium product, which is an ecosystem machine. The company claims that this machine along with the filter I am using will create a natural environment in the tank. So, there shouldn't be any water changes needed except for top-offs.
<Ah, well, it sounds as if this machine isn't real helpful. I'm *very* dubious about these machines that promise to remove the need for water changes. If you want to carry on using, then go ahead, but I'd still be doing 50% water changes each week simply to keep the pH and hardness at healthy levels. If the machine is removing some nitrate in the background, so much the better, but I personally wouldn't consider any machine an alternative to water changes.>
I set up this machine on June 1 and haven't really made any "reasonable" water changes. I started my first tank in February and now I have 3 tanks...
(still thinking about getting one more, just can't stop... love to watch fish swimming) I read lots of books, magazines and information on website to help me, as I am very new in this. I know regular water change is important, so while I am testing this machine I bought in Taiwan, I am still concerned about not making any water change at all. Therefore, instead of vacuuming gravel and making water changes, I used power vacuum to clean the gravel only, which took out the debris from the tank without taking any water out.
<The debris at the bottom of the tank is harmless. It looks messy, which is why we remove it, but it's the "end" of the food chain, and doesn't affect water quality either way. It's the *invisible* dirt that causes problems, the nitrate, nitrite, ammonia, phosphate, etc. in the water. These are things water changes remove. I just don't trust a machine to do this. So please, go back to doing water changes. It will make life easier for everyone.>
Since the machine was set up, everything has seemed to work fine until I found the PH has been continuously going up. I started to search some answers and information from books or website. What I was told is "Top-off water" would continuously add more and more minerals to my tank and cause PH to increase if my tap water is very hard. That is why I started to think "our hard water" is the cause and wanted to use a safe way to correct the problem.
<I think your analysis is sound. In "the wild" calcium carbonate is removed from the water in a variety of ways, for example by plankton turning it into what (eventually) becomes limestone. Some gets converted in CO2 gas as well. But in the closed system of an aquarium these "sinks" as they're called don't exist. The calcium carbonate will keep accumulating. Water changes keep the calcium carbonate level fixed, because the water going out is matches by the water going in. But if you're adding calcium carbonate in the top-up water while never removing any through water changes, then that calcium carbonate will just accumulate. Whatever the mechanism, I don't like this at all. Do the water changes!>
I still make water changes for the other 2 tanks, so the PH isn't that high like the 38 gallon one which has the special eco machine set-up. What I want to do is try to bring the PH back down to 8.0 by making some gradual small water changes using mixed RO and tap water. Once PH is 8.0 and stable, perhaps top-off water can be 100% RO water?
<See, you have experimental data! I think the "eco machine" sounds a fun toy to play with, but I'd be doing water changes as well to find a "happy medium" where I get good water quality *and* the right pH/hardness levels. I just don't believe -- at all -- any aquarium can be safe without *any* water changes. If such things worked, we'd all be using them. I'm not saying it's a con or dangerous, but I think you should use some common sense. It clearly is causing a problem here, and the fix is nothing more difficult than a water change. So do water changes... see what happens, and change your maintenance regime accordingly.>
The aquarium store in Taiwan I visited has several big tanks with eco machine in them. Water is very clear and tanks have been more than 4 years old. They did not make any water changes at all. That's what made me so interested in giving it a try... as if no water change is needed and fish can really live in a very natural environment; it's certainly a very relaxing/enjoyable thing to keep as many tanks as I like.
<Fish will adapt to all kinds of environments, given time. I read a story in an old TFH book about some marine fishes (Sweetlips, I think) that had been placed in an outdoor pond filled with salt water. This pond was somewhat neglected, and eventually rain had made the water so dilute in the pond that things like water lilies were growing. And how were the marine fish? Apparently just fine! They'd grown to a large size and were thriving and happy pets. Does this mean people should keep marine fish in freshwater ponds? Of course not, but it's an example of how fish can adapt given time. Your mollies have clearly adapted well to the 'eco machine' tank you're running, and since they're breeding happily, no harm seems to have been done. But if this was me, I'd be doing the water changes.>
Hope I cleared your questions in your mind... and the path I am going is right for my fish's well-being. Mollies are very "inexpensive", but I love them and want to make them happiest mollies if I can. I started with 3 mollies... now I have more than 160 in total. (Never managed to count them one by one though...)
<Mollies are excellent fish, among my favourites, and I'm glad you're enjoying them. They've been massively mistreated by the hobby in some ways, and too often I hear stories about sick mollies or aggressive mollies or mollies in too-small tanks.>
Thanks for your help and time in sharing your experience with me.
Kathy
<Well, good luck with it all. I heartily recommend doing a bit of experimentation with water changes to see if that helps. Cheers, Neale>

BIG pH swings - please advise! FW   7/9/07
Hi guys. What do you recommend to stabilize pH at a healthy level?
<Sufficient buffering mechanisms...>
I do not understand what my problem is! Do I have zero buffering capacity, or a LOT of it?
<Not much...>
The pH in my tank has been very low for a long time, even with regular water changes. My discus have been fine at the low pH-at least it has been stable. I have recently started mixing in a little treated tap water with the r/o for water changes. WOW! What a change in pH with the new water added! If my SMS122 controller can be believed, the pH increased today from 4.1 to 6.5 (it was a large water change)! I did a water change last weekend as well, using mixed water. Here is the thing: the pH was back down to that unbelievably low reading again in one week!
<Yes>
A couple of my discus seem to have developed ich now, surely from the monumental pH swings.
<Mmm, maybe a factor...>
I have increased the temp, added an bubble wand and began treatment today with Maracide (I already had some at home). What should I do to eliminate these very unhealthy swings in pH?
<Get, use an alkalinity test kit... develop a regimen of water changes that doesn't allow such swings...>
Would you follow the Maracide label directions: one drop per gallon of water, every 24 hours for 5 days (the discus are the only fish in the tank)? Thank you for your response.
<I would... Bob Fenner, who at one time handled 1-800 calls for the original owners of Mardel Lab.s>

Bacterial Hemorrhagic Septicemia / fin and tail rot  6/30/07
Hello,
<Hi there>
I have a 16 year old Silver Dollar that has the following conditions. Left pectoral fin is gone; the flap is there and flaps like crazy, but there is no fin attached.
<Mmmm, might grow back if not too far gone...>
Both pelvic fins are completely gone. The caudal fin is badly frayed (3 weeks ago was almost completely gone) and is strangely red at the base close to the fish body.
<Something amiss here...>
History; up until 6 weeks or so ago, I had the silver dollar in the tank with a Pacu.
<Ohhh>
The pacu was huge and out sized the dollar by ten times at least. One day I noticed that the silver dollar was missing most of its caudal fin and what was there was badly frayed. The pelvic fins were gone as well as was the pectoral. I assumed it was fin and tail rot and treated the tank with Mardel Maracyn Two. The caudal fin began to get better for about a week then went to worse again.
<... stress, bullying...>
I then thought that it was the pacu. Although the pacu never picked on the dollar in my presence I thought it was happening when I was not around. I wanted to get rid of the pacu any way since it was so big and messy to take care of. I found a home for the pacu at a LFS adoption tank and that left my dollar to her self. The caudal fin healed from almost nothing to about one-half but then quit and will not heal further. The other fins have not changed at all. I am patient and though that in time all would be well again so went out and bought 3 more silver dollars to keep the old one company.
Before getting the new dollars the old one ate well, but now the feeding frenzy and competition is causing the old dollar to swim faster to get her share, but with out the control of all her rudders she cannot aim correctly at the food and misses it.
<Provide more bulky food items... greenery that the impaired one can eat easily... Like blanched zucchini>
Also, she cannot maneuver well enough to keep up with the other dollars who are younger and smaller. This is causing me to revisit medication or some form of treatment before the dollar winds up dieing.
<... Medication not advised here>
My tank is 75 gallon, Ph - 6.8, nitrite - 0, ammonia - 0, Nitrate 20-40, GH 3d, KH <1d, total dissolved solids 300ppm, RO water conditioned with Kent RO right,
<I'd use less, let the TDS hover around 100 ppm>
Ph buffered with Kent Ph 6 and 7 (phosphates), and the temp is 25.5c.
My 1st question is this- I read that the redness near the base of the fins could be Bacterial Hemorrhagic Septicemia. Does it sound like it to you?
<This... is a condition... Need to seek out, address root cause/s... the trauma, "dirtiness" from the Colossoma... Takes time to heal...>
2nd, Can the pectoral and pelvic fins come back if I treat the fish correctly, or are they gone for good?
<Can regenerate>
3rd, what/how would you recommend treating the condition(s) with and should the treatment be carried out in a separate tank, or is the condition contagious, requiring that the entire tank be treated.
Many thanks!
Scott S
<I would try the change to foods with more bulk, lowering the TDS, soaking the food/s in a vitamin and HUFA mix like Selcon to boost this animal's immune system... Bob Fenner>

Re: Bacterial Hemorrhagic Septicemia / fin and tail rot   6/30/07
Hi Bob,
Thanks for the quick reply.
<Welcome!>
I'll take your advice and not medicate.
How do I lower the TDS?
<Mmm, either start with "cleaner" water or not add to it...>
I add chemicals when I do water changes as follows.
To 15 gal I add 1.5 tsp Kent RO Right,
<Leave most of this out... this should do it>
1 tsp Kent Ph Precise 6.0, 0.5 tsp Ph Precise 7.0, and 15ml Tetra Black Water Extract. That brings my TDS in the new water to 235. Still even then my GH is very low, between 2-3 dH, and the KH is so low I cannot measure it.
Would you add different quantities/products?
Thanks again,
SL
<Try cutting back on the RO product... try a level teaspoon of baking soda (Sodium bicarbonate) instead...>

Re: Bacterial Hemorrhagic Septicemia / fin and tail rot, Silver dollar...  6/30/07
Hi Bob,
You must have forgotten that I am using RO water, or I doubt that you would recommend that I only add 1 tsp of baking soda to 15 gal of it.
<I did not forget anything...>
On the label of the RO Right, it recommends 1 tsp per 10 gal for soft water. That is what I am currently adding. Also, on the Ph Precise I am following the label as well.
Since my fish has out-lived my dog, I must be doing something right with respect to water chemistry and husbandry.
<... what is your point?>
My quandary is in treating an old fish which has lost much of its finnage, and over an 8 week period has not shown much improvement despite a great deal of effort.
Your suggestion of more bulky food was a good one. The silver dollar seems to really like green beans, and since none of the other dollars pay any attention to them, the wounded one has them to herself and once again has a full belly.
Also, I have taken your advice on supplementing vitamins. I have no experience with mixing food, so I am adding freshwater essentials to the water to add vitamins. Hope this works in lieu of.
Thanks for your help,
SL
<Please... just use the indices, search tool. RMF>

Re: Bacterial Hemorrhagic Septicemia / fin and tail rot – 07/01/07
Bob,
<SSL>
What is my point you ask? Most of what I do with respect to maintaining my fish tank is based on information gleaned from posts on your web site and from your direct responses to my previous questions over the past 2 years.
I.e., RO water instead of tap, frequent water changes, softer water, discontinuing fish-slime additives, etc.
<I am in agreement with all of this>
Then, in this most recent volley of correspondence you suggest that I go to pure RO water without any additive other than baking soda
<Sorry for the lack of clarity... I would try decreasing the RO Right product by half ml.s per time/maintenance interval, and in addition, add the level tsp. of bicarb>
which would leave my tank with out any major or minor elements, no GH, and enough alkalinity to bring my Ph back up to 8.0. Why would you suggest this? It makes no sense to me in light of the other comments and suggestion on your site.
SL
<Do try this in a separate container... and measure the resultant chemistry... a day later. B>

pH mystery-please help!! – 06/27/07
Hi crew. Thanks for answering my previous questions regarding tank setup and stocking levels. I have a new question that has me completely baffled. I am completely stumped as to why my pH is sooo low.
<The tendency for all aquaria is to become acidic over time. What inhibits this is the buffering capacity of water (specifically, its carbonate and bicarbonate hardness) and the frequency of water changes. The simplest approach to declining pH is to just change more water, more often, assuming of course that your tap (faucet) water has a higher pH.>
I have a 55 gallon discus aquarium that is home to 8 discus (3-5") and a relatively large anubias barteri. Other plants have not faired well and were removed.
<Anubias is the Aspidistra of the aquarium plant world. I inherited a specimen that lived for TWO years in a tank with no lights!>
Present tank configuration is over a year old now.
<So should be stable.>
Recently, the pH reading on my Milwaukee SMS122 monitor took a dive.
Water changes did not move the pH, so I was convinced that the probe failed (again).
<Certainly possible. But also check calibration and good old fashioned user error. There's often an argument for using a simpler, if less accurate, test kit that delivers consistent results.>
I replaced it, but when I installed the new probe (after calibration) I was shocked to find that the pH reading was the same:
3.9!!!
<Dead fish would be here. Remember, the pH scale is logarithmic, i.e. pH 5 is 10 times more acidic than pH 6, pH 4 is 100 times more acidic than pH 6, and so on.>
I manually tested the water parameters, but the test kit that I have tests only down to pH 6. Of course, the water tested at the bottom of the pH scale.
<It is entirely possible for regular aquaria to dip below pH 6 to around 5.5 under certain circumstances. Usually, you'll notice plants wilting and snails heading for the surface of the tank. The fish will usually behave in obviously odd manners as well. Much below 5.0, and most fish will simply die. There are some acidophile fishes, such as Hemirhamphodon pogonognathus that enjoy such conditions, but the vast majority do not, Discus included.>
Nitrates were 10ppm (I know, it is time for a water change!) Ammonia was 0.25ppm, and no nitrites.
<The ammonia is lethal at this level. I'm staggered your Discus are alive, to be honest.>
Water changes are done with R/O water.
<Ah, what are you mixing the RO water with? You do need *some* hard water in there. Around 3 parts RO water to 1 part hard water (~ 20 dH) gets you water at ~5 dH which is about right for Discus. This gives the water at least some buffering capacity, enough to last between weekly or twice weekly water changes. Pure RO water has ZERO buffering capacity, and the simple background acidification will rapidly drop the pH. It isn't even safe to keep fish in pure RO water. Although the science is fuzzy about this, fish do seem to absorb some minerals from the water they drink.>
Do I need to do a really massive water change to move the pH back up, or add some treated tap water?
<You shouldn't ever *need* to do more than 50% water changes a week. Doing more water changes is a good idea, but if they're *essential* to keeping the aquarium stable, then something is amiss.>
I don't know about the chemistry of my tap water. I stopped mixing it in due to a terrible algae problem that I ended up resolving be completely breaking the tank down and cleaning it (before I got the discus).
<Non sequitur. Tap water doesn't cause algae. At the very least, you want to be adding maybe a 10-20% dose of Malawi or Tanganyikan salts to the water to get some background hardness. You're aiming for a pH around 6 and a hardness between 5-10 dH. There is absolutely no advantage to keeping the pH and hardness below this level, especially if you're having pH problems. Plants HATE very soft water, and that may be one of your problems. Most aquarium plants want a neutral pH and low to moderate hardness. Assuming lighting and CO2 are adequate, this may be a key problem for you. Once you have thriving plants, algae pretty much goes away by itself, almost regardless of background levels of nitrate and phosphate. It sounds simple, but it's actually true.>
OR, is it time to break the tank down again and clean???
<No. Review what you're doing in terms of mixing RO water with hard water: I'm 99% sure that's the source of your problems.>
This is really freaking me out and I don't know what to do!!! The fish must be acclimated to it-they are eating and behaving normally as far as I can tell.
<Yes, fish can acclimate to surprising things. I've heard of marine fish (sweetlips to be precise) being kept in outdoor pools that were so low in salt that freshwater plants were growing. But still, the idea is to try and create stable conditions, because in the long run that's what most fish like best. The precise pH and hardness values are secondary in importance compared with actually keeping them steady over time.>
Bad timing (or maybe not) for this problem to arise. I am in the process of researching what I need to upgrade to a 90 gallon tank. I will supplement filtration with a HOT BioWheel type filter, maybe an Emperor 400.
<The filter is probably a good idea for an upgrade, given the background ammonia level, but -- below pH 6.0, biological filtration slows down dramatically, and it stops once you reach pH 5.0. Another good reason to keep the pH at 6.0.>
ANY help will be gratefully received!! Thank you very much.
<Hope this helps, Neale>

pH and water flow  5/17/07
Crew,
<<Hi, Erik. Tom with you.>>
Great site, thank-you.
<<Thanks, Erik. Glad to hear we’ve been helpful so far.>>
I have a 30 gallon tank with Eco-Complete as substrate and nothing else in it. I use RO/DI water. My Pinpoint pH monitor reads the pH as 7.2 and up with the Whisper 40 running (only has carbon in it) and reads 6.75 and lower with the filter off and not flowing at all. Why?
<<Well, now both of us have an issue to deal with. Your issue is that pH monitors don’t work well in purified (RO/DI) water. Mine is trying to explain, in simple (?) terms, why they don’t. First, and not surprisingly, RO/DI water has very little in the way of buffering capacity which means that pH can change quite readily, up or down. Simple enough. Second, commonly our pH is affected by the absorption of CO2 from the atmosphere. This is why you can expect pH to typically decrease over time since dissolved CO2 in the tank lowers pH. How quickly this takes place depends on a wide number of factors but, once again, this can depend, in part, on the buffering capacity of the water. In our homes, CO2 levels can be, and typically are, higher than outdoors yielding a higher concentration of the compound in the air and, therefore, greater opportunity for our tanks to absorb it. (RO/DI water generally runs in the pH range of about 5-7 depending substantially on the level of dissolved CO2.) Third, CO2 is “driven” out of the water by agitation such as what you might create with airstones, UGF’s, HOB filters, etc. Though this doesn’t even scratch the surface of a highly complex topic, I believe that what you’re seeing is the absorption/dissolution of CO2 in your tank caused by calm periods (filter off) resulting in increased CO2 absorption (lower pH) followed by active periods (filter on) resulting in decreased CO2 (higher pH).>>
Also, the readings on the pinpoint monitor fluctuate a tenth of a point constantly, it is never pegged. I know constant pH is better than a specific reading and I can't get the pH to stay at one reading even in this small tank.
<<The greater the precision of the instrument, the more likely it will be to show variances, Erik. You might think of it like the “refresh rate” of your computer monitor. The higher the refresh rate, the more screen “flicker” you’ll observe. Your Pinpoint monitor is constantly refreshing its readings. In conjunction with what I’ve already discussed, I’d be very surprised if it weren’t constantly fluctuating. A very nice piece of gear but it has drawbacks in this particular set of circumstances.>>
Respectfully,
Erik
<<Hopefully this will shed a little light on your situation, Erik. Best regards. Tom>>

Phosphate + pH, FW...   4/30/07
Hey guys,
I should have asked this straight out when I asked about my phosphate question, sorry about the dual emails. I mentioned I was lowering my pH with Seachem's Acid Buffer. The problem is that my pH constantly raises no matter how many times I add the buffer. I have a Pinpoint monitor and can see it go up slowly but surely every single time. My pH from the tap is high, around 8.0, but I thought the Acid Buffer would lower it and keep it low.
<Mmm... you need to understand the relationship of (the unfortunate term) alkalinity... or buffering capacity... as it relates to pH... You likely have a situation with chemical species that "rebound" the pH... from your source water... perhaps the decor, substrate... Please read here: http://www.wetwebmedia.com/FWSubWebIndex/fwph,alk.htm
and the linked files above>
But up it goes. Once I add fish and plants I would have to add Acid buffer every single day to keep the pH at 6.8-7.0 as I want it.
<You don't want to do this... Such changes should be made gradually... with water adjusted outside the system... not by pouring in chemicals into the main/display tank...>
If I went away for a weekend it'd be 7.5 or higher in a day or two without it. Not good for tankmates I'm sure. Any help? I truly appreciate what you folks do for us in the hobby.
Erik
<Read on my brother, read on. Bob Fenner>

pH and Alkalinity too high - Goldfish... please help!  4/26/07
Hi guys,
<Greetings>
I am in need of professional help! Your site is great, have been reading a lot and doing some of the suggested things, but doesn’t seem to be working. Here are the specs:
-I have a 10 gallon freshwater tank with a BioWheel filter for a 30 gallon tank
-The tank has 1 African Dwarf Frog, 2 Orandas and 1 black Oranda (?) and one regular goldfish (aka feeder)
– the last was a birthday gift for my son which is how this whole tank thing started!
<The frog is a tropical animal, the goldfish coldwater, so really these two shouldn't be together.>
When we first got the tank in late February, there was the frog, 1 small tetra, 1 black Oranda (not the same one now) and the feeder fish from above. The black Oranda died as well as the tetra (it was eaten by the new black Oranda). Anyway, I am such a mess! I don’t know what to do.
<Is there a heater in this tank? If not, more likely the tetra died from the cold, and the Oranda ate the corpse. Goldfish aren't particularly good at catching small fish. They don't have any teeth in their mouth, for a start.>
Beginning of this month, the remaining birthday fish were 1 ADF, 1 tetra and 1 feeder goldfish. They were doing well for well over a month, tested the water for Nitrate, Nitrite, Hardness, Chlorine, Alkalinity and pH. Everything was normal except for pH and Alkalinity – they were high.
<When you say "normal" what are the actual numbers? Should be ammonia, nitrite, and chlorine at 0; nitrate under 50 mg/l; hardness around 10-20 dH; and pH around 7.0 or so.>
I tested my tap water and both the pH and Alkalinity were also high - which I use for water changes after leaving a 2 gallon pitcher of water and a tsp of AquaSafe on the counter overnight.
<You don't need to leave the water sitting overnight. The dechlorinator works virtually instantly.>
I figured it was OK since this is the same water I have been using and my fish were fine.
We went to Petco and bought 4 Orandas. I know now that this was way too many fish for the 10 gallon tank.
<Took the words outta my mouth...>
But they didn’t tell me this at Petco. Anyway, came home, floated the bag on top for 20 minutes and then released the fish into the tank along with the water from the bag (I know that this was wrong NOW also!).
<Good!>
I also bought an ammonia monitor for the tank. I added the fish and it read “safe”. The second evening I went to a wedding and came home at 1 AM and it read “TOXIC”.
<Too many fish for the tank, too many fish added at once.>
Did some research b/c I did NOT know what to do…I found your site via google search and did an Emergency 50% water change. Still toxic ammonia levels in the AM. I did 25% water changes daily for 3 days and the ammonia came down by itself – I didn’t use anything aside from AquaSafe for the replacement water.
<Goldfish are, if not THE messiest fish kept by aquarists, they're certainly in the top three. You need a filter that turns the water over something like 6 times per hour (a regular tank will get by with 4 times per hour). In other words, goldfish need far *more* filtration than the average tropicals, and hence are *more* expensive and difficult to keep than, say, danios.>
Anyway, I thought everything was OK. I took some water from the tank and went to Petco b/c one of the Orandas was hanging out at the bottom of the tank and I know this isn’t a good sign.
<Indeed not.>
He tested my water and the ammonia was 0. Same for everything else but he said my pH was way too high. I purchased a product called “Proper pH 7.5”, followed the instructions which were to just put one packet in the tank.
<Where was the pH before? If over 7.5, then yes, you're way off base here. Also bear in mind the higher the pH, then the more toxic ammonia becomes. It sounds like you should be doing 50% water changes each day, to be honest. What is the pH of your local water supply?>
Tested a day later, ph still off the charts! Used another packet of perfect pH, tested a day later which was yesterday morning, ph still too high!!!!!! Yesterday I went out briefly and when I came home, one of the Orandas had died. I took him out and was super frustrated. After all, this was all a birthday gift for my son and I had NO IDEA that keeping a freaking fish tank would be THIS HARD & EXPENSIVE!
<It isn't hard or expensive done properly. But sadly, you are one of the millions who think (are told by retailers) that goldfish are good to start with. They're not. They are only marginally less demanding than coral reef aquaria, and I can think of a few marine fish that are easier! Goldfish are easy peasy in ponds, but difficult in aquaria, especially small aquaria. Repeat after me: goldfish are pond fish, not aquarium fish.>
Which brings us to today, tested pH first thing this morning, still too high (8.4) and total alkalinity is 300, also tested ammonia and it is somewhere between ideal and safe…less than .25.
<No. The only "safe" level of ammonia is the "ideal" level, ZERO. Anything else, even 0.25 mg/l, is enough to kill fish. Period, end of story. Anything else is like discussing safe gunshot wounds... ain't any such thing.>
Now another Oranda is hanging around the bottom, I think he’s next.
<Yep.>
I just did another 25% water change and have not fed them since yesterday AM. They seem more active. One looks like it has a hole on head. I have attached a pic, please take a look.
<The wound on the front? Looks like mouth fungus or something to me. Difficult to say. Either way, it's a product of poor water quality, and while easy enough to cure using anti-Finrot/fungus remedy, it'll keep coming back while your aquarium is as noxious as this.>
My questions:
1. Should I be concerned with high pH and Alkalinity?
<Yes.>
2. If yes, how do I bring it down? Proper pH 7.5 did nothing!
<Keep doing water changes if the pH is well above the water supply pH. You can't bring the pH to a lower value than your water supply, so if you have pH 7.5 out the tap/faucet, that's as low as it'll go.>
3. Is that a hole on the white and red Oranda's head? Or is that just how they are? I read about Hole in the Head – a disease? Should I quarantine the fish? Is it contagious?
<It isn't "Hole in the Head", it's merely a head wound. Treat as mentioned above. Not contagious, but the poor water conditions could/will cause similar things in other fish.>
4. How often should I feed these guys? First I was told (all by Petco employees), twice a day, then every other day, then once a day and was most recently told twice a day AGAIN, but I read not to overfeed fish, especially goldfish – please advise
<Fish don't die from overfeeding. Luckily for them, they poop out anything they don't need, so they don't normally get fat. BUT... decaying food/faeces create ammonia, and ammonia can kill the fish. Ergo, your job is to give enough food for the fish be healthy, but not so much it decays in the aquarium. At this stage, I'd be feeding once every TWO days until the water quality is fixed. After then, once a day, as much as the fish eat in 2 minutes, siphoning out any uneaten food.>
5. I have a very thin layer of pebbles on the aquarium floor, two artificial plants and two decorative columns…I read that the décor can sometimes cause high Alkaline – is this true? Should I take them out?
<pH will go up if the decor is made of limestone or similar, i.e., something calcareous that dissolves. Otherwise, provided it is sold as an aquarium ornament, it should be safe.>
6. Do I continue water changes? If so, how much, how often?
<Yes, 50% daily. More if possible. Certainly no less. Then take back all the goldfish, and swap for something suitable for a 10 gallon tank. I'd suggest guppies or danios. Add two the first week, then two more 2-3 weeks later, and so on. These fish need a heater as well as a filter, but being smaller, they are less polluting and all-round easier to keep than goldies.>
You know what’s amazing? The feeder fish that cost 10 cents is thriving! And the frog also seems fine.
<This is evolution. Mother Nature breeds her fish for survival, and feeder fish have all the genes nature gave them. Poor conditions on the fish farms mean only the fittest survive, and hence feeder fish are robust, those that survive anyway. Fancy goldfish are bred for looks. Humans are usually hopeless at spotting the good genes, so we end up with pretty but flimsy fishes like fancy goldfish, fancy guppies, Siamese fighting fish, etc. HOWEVER, feeder goldfish can carry lots of nasty diseases, so while not the immediate problem here, you should be aware of this. In life, you get what you pay for, a 10-cent goldfish is hardly going to have lived a hygienic, pampered life, is it? It's the aquarium equivalent of factory-farmed chicken.>
Please tell me what to do.
<The usual: buy/borrow an aquarium book. Sit down, read. Then swap out the goldfish for fishes better suited to aquarium life. Alternatively, get a suitable tank for these fish (30 gallons plus) and a BIG external filter.>
Otherwise, I feel like I am just waiting for them to die and if they do, I give up, I will not attempt to do this again.
<Not everyone has the patience, compassion, self-discipline to look after animals responsibly. If these traits aren't part of you, then I agree, take the fish back and get some pet rocks or something. BUT, if you're willing to step back, examine the problem, correct the mistakes, and then put what you learn into practice, I can guarantee you some of the most educational and rewarding experiences out there. Your move.>
Thanks,
Sabina
<Cheers, Neale>

Re: pH and Alkalinity too high - please help!  – 04/29/07
Hi Neale,
<Hello Sabina!>
Thanks for all the info!  I did indeed take the goldfish back to PetCo and they took them back no problem, got a full refund, even for the Oranda that passed away.
<Very good.>
Anyhow, this one guy at Petco is very good, his name is Matt. He said that my fish had parasites and fungus.  I am not sure what caused this...
<External fungus is quite common on goldfish when kept in improper conditions. Internal parasites are *far* less common than many fishkeepers believe. Yes, they occur, but most of the strange swellings or cases of emaciation that aquarists put down to "parasites" are actually caused by problems with water quality and diet.>
I live in an area with very hard water so we have a water softener installed.
<Hard water doesn't bother goldfish. Many aquarium fish positively thrive in hard water: livebearers, rainbowfish, glassfish, many cichlids, some killifish, even a few tetras like x-ray tetras! There are also lots of plants that love hard water, such as Java fern, Vallisneria, some Amazon swords, even some Cryptocorynes like C. ciliata. So hard water isn't a bad thing. Just choose your livestock carefully.>
I wonder if the problem was that in addition to the water softener, I was adding AquaSafe to soften the water even more?  Would this make alkalinity and pH rise?
<The combination of softened water (which often contains a lot of sodium) plus ammonia could cause pH problems. Personally, I always recommend against changing water chemistry. Often, it creates more problems than it fixes unless you know exactly what you are doing. The other huge plus to hard water is that it is inherently pH-stable. Most fish will adapt to a given set of water conditions so long as changes are gradual. Altering water chemistry in an ad hoc way, even to the "better", can stress fish quite easily. So my honest advice is this: just use the unsoftened water, adding *only* dechlorinator. Choose species that do well in hard water, and work from there.>
I started from scratch.  I emptied the entire 10 gallon tank.  Washed the pebbles with hot water, filter cartridges, BioWheel, artificial plants, the whole nine yards.  Put them back into the tank.  My question here is - Do I need to use "cycle" by Nutrafin if I am using old filter media that was rinsed?  Please advise.
<Depends on how well you cleaned the media. If you cleaned it under hot water or even cold tap/faucet water, then yes, you need to cycle the tank again. If you cleaned the filter media in a bucket of aquarium water only, then probably not. Either way, don't "assume" anything -- add one or two fish/frogs, do nitrite tests, feed cautiously, do water changes, wait a week or two before adding anything else, and keep repeating this process.>
I also had to put my African Dwarf Frog in the freshly changed tank.  I had no where else to put him and he jumps out of bowls!  Wish I had thought of the poor guy earlier and purchased him a separate little mini aquarium for the time being...but forgot all about him :-(
<Oops.>
Question - can the frog cycle the tank?
<In theory, yes, but dwarf African frogs are small, so I'd be adding also one or two guppies or danios as well.>
I tested the water before I put the frog inside, here are the results:
Nitrate 0
Nitrite 0
Hardness 75
Chlorine 0
Alkalinity 180
pH can't really tell - between 7.2 and 7.8
<OK, the hardness level is I assume mg/l of CaCO3. That's quite soft. The pH is slightly alkaline to moderately alkaline. Soft, alkaline water is an odd combination and not really ideal for anything. The problem with domestic water softeners is they add other minerals you don't test for (such as sodium salts) which is why you don't drink the softened water. I say again: just use the plain unsoftened water. Hard, alkaline water is fine for things like guppies, dwarf Mosquitofish, and platies that would do well in a 10 gallon tank.>
These are the results without me adding anything to the tap water (which is already softened). I need to know ASAP if I should add "cycle" even though I used the old filter cartridges?
<I'm dubious about the product "Cycle" having heard many times from people who found it didn't work. Use it, don't use, but either way assume nothing and test water quality regularly and add stock slowly, just as if you were cycling the tank the old fashioned way.>
And should I be worried about my little frog?  He seems to be EXTREMELY happy.  He has the whole 10 gallons to himself and he is jumping all over the place.  He seems fine.
<Okey Dokey.>
And last but not least, I still do not really understand this cycling process thing.
<Cycling is FUNDAMENTAL to keeping fish. Understand cycling, and everything else is EASY. Have a read of this: http://www.wetwebmedia.com/FWSubWebIndex/fwestcycling.htm and buy/borrow any decent aquarium book for more.>
I think in the end, my nitrates need to be 25+ -- that is considered cycled and safe to add fish?
<Nitrate level irrelevant to cycling being completed. You can have nitrates BUT ALSO ammonia and nitrites, in which case tank is uncycled. Measure ammonia and nitrite, and when they are zero, then you're cycled. Nitrate levels of 50 mg/l or more are perfectly safe for most freshwater fish. For the most part, you don't even need to test them: just perform weekly 50% water changes and the nitrates will keep at safe levels automatically.>
Will cycling happen quicker in my tank since I used the older cartridges?
<In theory, transferring live filter media from one tank to another tank kick-starts the biological filtration in the new tank dramatically, often cycling the tank instantly if enough media is used. HOWEVER, that depends on the live filter media being still alive when installed. Washing filter media in anything other than aquarium water kills most/all bacteria.>
I am so sorry for all these questions but I do NOT want to be knows as the fish killer!
<A very good intention. So, read some more, select some hardy, hard-water tolerant fishes, and press on.>
Thank you in advance for all your time & help! Sabina
<No probs. Cheers, Neale>

High pH, FW    4/21/07
Hi, Crew (Sorry for poor English)
<Hello! You English is fine, by the way.>
I keep fresh water fish for about 7yrs and never had problem with pH. My tap water has pH about 6.8. Few weeks ago I did rearrangement in my tank and bought some rocks from my LFS (they told me it's safe and do not affect water chemistry). In a few days I got very cloudy water.
<Sounds as if the rocks were either [a] dirty or [b] decomposing. If they are dirty, then washing well should remove silt and dust. An old trick is to place things in the cistern of the lavatory for a week or two. With each flush, they get a bit cleaner! Of course, this assumes the water in the cistern is regular tap water, and not treated with chemicals or otherwise unsafe for the fishes. Some rocks will decompose rapidly when they get wet, usually because they have a high clay content. Not much you can do to stop this.>
I remove rocks, went to different LFS and bought different kind of rocks. (Total I spent for rocks about $60 :-) ). Water became clear.
<When buying rocks, it helps to identify them. Some rocks are almost always chemically inert: grey slate and granite for example. Others are safe, but will raise the pH and hardness: tufa rock for example. Yet others will raise the pH and hardness but are dangerous if they have seams of metals or other contaminants: limestone for example. If in doubt, go with "artificial" rocks.>
Today I did regular water change (about 20%). After water changed I noticed that my fish became much happier and more active (2 angels and 2 red parrots). So I did water test:
Ammonia-0
Nitrite-0
Nitrate-10ppm
pH-7.8
Something wrong with the rocks. How can I check which of the rocks affected pH? Should I remove all the rocks immediately? Thank you for your help.
<The standard test is to add a few drops of acid (e.g., vinegar) to the rock in question. If the rock fizzes, i.e., produces Carbon dioxide, then the rock contains calcium carbonate and is going to raise pH/hardness.>
Mark
<Cheers, Neale>

pH shock, FW  – 03/18/07
Dear Crew,
<<Hello, Kris. Tom here.>>
Does a routine carbon change in my freshwater tank cause a pH shock and if so, how do I get around this?
<<By “pH shock”, I’m assuming you’re observing a significant rise in pH, Kris. Changing the carbon in your filter shouldn’t affect your tank’s pH levels. If this “appears” to be happening, I’d surmise that it’s occurring in conjunction with water changes, which can definitely affect your pH readings. If your water is inadequately buffered, pH can drop significantly in a short span of time. Even with adequate buffering in your source water, you can expect to see a drop in pH levels after a while. A water change, particularly if it’s a large one, will send pH levels right back up. Kind of a pH roller coaster ride. You do want to avoid the temptation to chemically alter your pH in either direction. This typically creates more problems than it solves. A simple/safe way to maintain pH stability is by making smaller, more frequent water changes. Kind of takes “Nature” out of the picture and puts the control back in your hands. Best regards. Tom>>  

Freshwater high pH    02/17/07
To The WWM:
My tapwater has a pH of 9.1
Should I add some chloridic acid in order to achieve a better value for angel fish (freshwater) or could you suggest another method?
<Another method... starting with "cleaner" water through RO, other filtration, using other products/acids, peat et al. filtration...>
When adding top off water is necessary to adjust previously the pH using acid?
<Best to adjust in some way ahead of time, yes>
Could you suggest also the acid dose per litre?
<...>
The RO/DI water can do something about it? Or it just influence the water hardness?
Thank you very much for your help
Flávio
<Please read here: http://www.wetwebmedia.com/FWSubWebIndex/fwph,alk.htm
and the linked files above. Bob Fenner>