Growth on Gourami's mouth 09/15/09
Hi , I have a community tank with 2 Pearl Gourami fish and on the male one he has a white cotton like growth on his mouth.
<Likely one of two things, a fungal infection, or else something called Mouth Fungus that is, despite its name, a bacterial infection. Now, both of these infections look similar, but there are clues that tell them apart. True fungal infections are typically composed of fluffy white threads, often likened to cotton wool. Mouth Fungus (also known as Columnaris) tend to be more off-white to grey, somewhat slimy-looking, and more like a lumpy growth than tufts. Some medications treat both: for example Seachem Paraguard and eSHa 2000, in which case there's no need to differentiate them. Avoid therapies based on either salt or tea-tree oil (e.g., Melafix) as these tend to be unreliable.>
He has been acting weird and not eating properly.
<Both Mouth Fungus and regular fungal infections are typically caused by one of two things, often in combination. Physical damage, such as fighting or careless handling allows secondary infections to set in. Ordinarily the fish's immune system would deal with these, but in tanks with poor water quality, the immune system is weakened, and hence the infection gets out of hand.>
I am not sure what the growth could be or what I should do. I have a 23 gallon tank and all water levels are fine.
<Because this fish is clearly sick and suffering from either fungus or Mouth Fungus, I honestly don't believe the "levels are fine". If they were, your fish wouldn't be sick. To recap, Pearl Gouramis will need water with a stable pH between 6 and 8, hardness between 5-20 degrees dH, zero ammonia, and zero nitrite. Males can be mutually aggressive, and in a 20 gallon tank shouldn't be kept together.>
Thanks ,
Sonny
<Cheers, Neale.>

Treating Velvet and Mouth Fungus with Lace Synodontis in the tank – 09/08/09
Hi there,
<Hello,>
My son pushed too fast to set up his tank and now has problems with velvet and mouth fungus, and possibly some ich. There are three Danios that definitely show signs of both the velvet and mouth fungus.
<I see.>
The problem is complicated by the fact that he also has a very sweet and lovely large lace Synodontis catfish who we have totally fallen in love with and she seems very sensitive to medication.
<Yes, this species (genus, family) can be. Removing to a quarantine tank would be one solution.>
The tank is 50 gallons and these are all the inhabitants: 5 small green tiger barbs, 3 large Danios, the lace Synodontis, a small bristle nose catfish, a small clown loach, an Ngara, a blue dwarf Gourami, and an algae
eating shark. It is a planted tank, but the plants can be replaced if they don't survive treatment.
<Bit of a mixed collection! Not entirely convinced this selection of fish will work in the long term. Ngara, for example, are Aulonocara cichlids, and semi-aggressive, as well as fussy about water chemistry. Clown Loaches don't stay small for long; adults are some 11 inches/27 cm long. And so on.>
Do you have any suggestions for how we can eliminate the mouth fungus and the velvet? We tried Rid Ich+, but the Synodontis seemed very bothered by it.
<Various catfish are indeed sensitive to copper and formalin, so that limits the range of options. Ordinarily, you'd treat Ick and Velvet using a salt/heat method (raise temperature to around 82-86 F, add 2-3 level
teaspoons of tonic salt per US gallon of water. Run thus for about two weeks. Keeping the tank dark (cover with a blanket) also helps, since the free-living stage needs light.>
We have also used Melafix, which keeps the mouth fungus down, but does not seem strong enough to totally cure it (and doesn't seem to do much, if anything, for the velvet).
<Mouth Fungus is bacterial, and Melafix is a weak bactericide, at best. Use a proper antibiotic such as Maracyn if you can, or else an antibacterial based on an organic dye if antibiotics aren't easily available in your region. I happen to like eSHa 2000, but there are numerous other brands, such as Seachem Paraguard that work well too. Read the instructions, and don't forget to remove carbon (if used) when necessary. Don't mix medications, although you can use *one* medication alongside salt without problems.>
Thanks very much for any help you can provide.
<While Velvet comes in with new fish, Mouth Fungus is triggered by environmental issues, and this is something you must review. You can keep treating the fish as much as you want, but if the underlying causes
(typically poor filtration, overfeeding, and/or overstocking) are present, the problem will keep coming back. Cheers, Neale.>

Re: Treating Velvet and Mouth Fungus with Lace Synodontis in the tank   9/9/09
Neale,
<Constance,>
Thank you so very much for your advice and for responding so quickly.
<My pleasure.>
We'll get on it today. This is a fairly new project and my kid was not properly changing the water and filter at first, which is a big part of the problem we are dealing with now. We are on top of the water quality now.
<Good stuff.>
We'll start cycling a sick tank, but in the meantime we'll try the aquarium salt treatment and antibiotic. (And maybe we'll move Ngara into the second tank after it is cycled and when it isn't being used as a hospital because you are right that s/he is aggressive.)
<Indeed; a nice species, a very nice species in fact, but does need a Malawi community setting really, perhaps mixed with the superb Labidochromis caeruleus "Yellow Lab" for a nice contrast.>
I just want to double check that adding this much aquarium salt will likely be tolerated by the lace Synodontis and bristle nose catfish. I have read that some catfish cannot deal with salt.
<It's a misunderstanding about the salt. For a start, at least two families of catfish live in the sea! Several other families have species that enter brackish water. In any case, the amount of salt you are adding is trivially low. Let's say you add 3 level tsp of salt. It's a little under 0.25 oz per tsp, so that's about 0.75 tsp per US gallon. Normal seawater contains about 4.75 ounces of salt per US gallon, so what you're adding to your aquarium is actually about one-twentieth the salinity of normal seawater. There's probably more salt in a can of soda pop than that! It's really a very, very harmless dosage. While you wouldn't want to use this addition of salt on a permanent basis, for a couple of weeks it's a safer way to treat against Ick and Velvet that copper- and formalin-based medications.>
With gratitude,
Constance
<Good luck, Neale.>

Re: Treating Velvet and Mouth Fungus with Lace Synodontis in the tank   9/9/09
great! any place I can order the eSHa 2000 in the US? Or should I just settle for Seachem ParaGuard?
<So far as I know, eSHa products are exclusively sold in Europe. Seachem Paraguard is at least as good, and while it doesn't contain copper or formalin, it does contain malachite green, so if you do decide to use it,
watch your catfish carefully. Malachite green isn't copper (despite the name) but an organic dye, and while these should be harmless, you never know.
http://www.seachem.com/Products/product_pages/ParaGuard.html
eSHa 2000 contains a different organic dye, and while my Synodontis (and pufferfish) never complained, as always, your own mileage may vary. You might decide to opt for Maracyn or a similar antibiotic because of this.
Cheers, Neale.>

Bristlenose with fungus? – 08/04/09
Hi,
<Hello Kate,>
I have a bristlenose Pleco who has been sharing a 40-gallon aquarium with a handful of African cichlids for the past 3 years. They normally get along quite well; the cichlids ignore the Pleco (but maybe there's a first time for everything...), and he usually stays out of sight in a cave among the rocks during the day.
<Ancistrus are at risk of being harmed when kept with the more aggressive African cichlids, particularly Mbuna.>
I had noticed that algae had been building up on the glass over the past few days, but I assumed the Pleco was holding out for an algae cookie, as he tends to do - he's a bit spoiled in that respect! This evening, when I moved the rocks around to do my weekly water change & vacuum the gravel, I was horrified to discover that the Pleco's snout was a mottled pale colour, and that his bristles were almost all gone. His snout also has a coating of some fuzzy white stuff that looks like fungus. He usually scuttles out of the way when I clean the tank, but this time he barely moved. He looks awful!
<Assuming it's fungus, which looks like white cotton wool threads, treat accordingly.>
I had some Maracyn (about a year old - is this ok?) on hand, so I dosed the tank with that,
<Unlikely to cure Fungus. The same goes for Melafix (tea-tree oil). You do need a genuine anti-fungal medication.>
and I added a bit of extra aquarium salt as well.
<Don't. Salt won't help, and some African cichlids, such as Mbuna, may develop bloating when exposed to saline conditions.>
All of the water parameters are normal.
<As in...? I need numbers, not judgments! Fungus is caused either by poor water quality or physical damage. So, check firstly you have 0 ammonia and 0 nitrite. Secondly, think about the companions. Some African cichlids are harmless enough when kept with Ancistrus, notably Kribs. But Mbuna would be a very bad choice of tankmates, since they'd persistently nip and buffet these poor catfish, causing physical damage.>
I realize that a separate tank would probably be best, but my old 10-gallon tank is in storage and doesn't have a proper cover (and with a new kitten in the house, this just spells disaster). Is it ok to continue dosing the main tank? Is the treatment even worth it?
<Yes. Fungus clears up pretty well.>
The Pleco seems to be in really bad shape and I don't want him to suffer needlessly if it's a lost cause.
<Well, the "suffer needlessly" bit assumes you're going to euthanise a fish in a way that doesn't cause pain. See here:
http://www.wetwebmedia.com/euthanasia.htm
>
Thanks for any advice you can provide,
KW
<Cheers, Neale.>

Platies and Gourami poorly   7/31/09
Hello,
<Hi,>
I have a problem with my tank and wonder if you can help.
<Let's see.>
My system is a rio180 with the internal filter as supplied, tank has 14 x pentazona barbs, 3 SAE's, 3 Danios, red tailed black shark (as yet not harassing anyone), one upside down catfish, 3 Columbian tetras, 4 rosy tetras, 2 diamond tetras, about 10 platies, a Moonlight Gourami and a Pearl Gourami.
<All sounds fine, though the Red-tailed Shark is a bit big (and a bit aggressive) for this species. I'd also make the point that some of these fish are fairly gregarious. Upside-down catfish for example should be in groups of three or more, otherwise they'll be very nervous and shy.>
About 6 weeks ago I had new platies, and the moonlight Gourami. In Qt the platies had a bit of fin-rot, which took about 2-3 weeks to clear up fully (treated with eHSA2000 in the end). The Gourami had a little white lump on one feeler, but nothing else occurred, so after 3 weeks in QT I transferred them to the main tank.
<OK.>
Shortly before they transferred I treated a platy in the QT from the main tank which had some signs of fungus on her back (not on the fins, just on her body). She responded well, and all fish went in to the main tank together.
<I see.>
Unfortunately after about 2 weeks in the main tank, the platy I had treated for fungus died. She got progressively thinner, and despite showing an interest in food, wasted until I euthanized her as she was sitting on the bottom for about 3 days straight.
<Does sometimes happen; may be the "wasting disease" that sometimes affects livebearers.>
About 10 days ago I noticed that about 5 platies had varying amounts of tufted white stuff on their bodies, and pale patches on their fins. Rather than treating them for fungus in the QT, I read up and decided that after removing the carbon I was OK to treat in the main tank. All bar one platy is now looking a lot better, I treated them for 3 days, observed, and as there was little improvement, continued for another two days as directed on the instructions for eHSA2000. That was now four days ago.
<Now, if you're finding all of your livebearers are getting patches of fungus, that's something else. Platies are generally hardy, but they do need hard water, and if your water is soft and acidic, they will be persistently sickly.>
Now I have one platy with what looks like pale bits / almost translucent patches, sitting on the bottom, and another with tufts of white on the body coming back.
<Not good.>
To make matters worse my beautiful moonlight Gourami has what looks like an ulcer on her mouth, about 1-2mm across, and is not feeding. The ulcer is pinky-white with a reddish patch, no tufts of white or anything.
<Sounds like incipient Finrot or similar.>
I carried out a 30% water change this morning after testing and finding a nitrite spike of about 1ppm, ammonia 0, nitrate 20. Could the eSHa have caused the spike? What can I do for my Gourami? And why are my platies getting white tufty bits, despite repeated treatment with eSHa (which suggests to me that this is the wrong treatment, or that I have a pathogen I am not getting shot of)
<Given you have a variety of fish that are exhibiting bacterial and fungal infections of an opportunistic type, I'd be thinking about water quality and water chemistry issues, perhaps both. For the selection of fish you have, you're after the following values: pH 7.5, hardness 10+ degrees dH.
This may require hardening the water a bit if you live in a soft water area. Ammonia and nitrite should be 0, all of the time. If they're not, review filtration, stocking density, and whether your filter is adequate for the task (or properly maintained). The Rio 180 has a competent filtration system, but the pump is a little on the weak side, and water flow can easily diminish if the sponges are clogged.>
Any suggestions / treatment for the Gourami would be very much appreciated.
I will test water again tomorrow - when I tested after the water change there was no detectable nitrite or ammonia, and very low nitrate.
Thank you so much,
Regards
Sarah
<Cheers, Neale.>

Re: Platies and Gourami poorly   7/31/09
Hi
Thanks for the quick reply. I don't have test kits for PH and hardness at present - we live in south Herts (Chorleywood) and the water here is generally very hard; we use a water softener for the majority of the house (not for the tap where the tank water comes from though, I hasten to add).
<I see. I'm in Berkhamsted, so I imagine my water is much the same as yours. I mix it 50/50 with rainwater, and find it works for most things very well.>
I will see if I can get a kit when out today and test the water. I have a spare hang on the back Fluval U2 filter I was given I think I will plug this in as well, to see if it improves matters, and will give the filter sponges a rinse out in tank water.
<Yes, do this. The Juwel 180 is a good tank -- there's one right here next to me by the computer -- but the filter on these tanks generally is not well suited to messy fish. Eventually, I ripped mine out and instead use a pair of canisters, an Eheim 2217 and a Fluval 104. In any case, do check the sponges, and do look to see if any of the inlet slots on the black filter module are blocked, clogged with gravel, or otherwise restricting water flow.>
Is there anything you can suggest for the Gourami- he's not eating and the ulcer on his lower lip is looking quite sore.
<To be honest, eSHa 2000 is by drug of choice for this sort of thing. You might do a daily saltwater dip (35 grammes non-iodised salt in one litre of aquarium water) for a couple of minutes, as this sometimes helps to keep infections clean, a bit like saltwater gargles for mouth ulcers. Dunk the fish only until it shows signs of severe distress (like rolling over) and then return to the aquarium.>
Water chem. today was ammonia 0, nitrite 0, nitrate 5 - but I did do a 40% water change yesterday.
<Much better.>
Thanks
Sarah
<Cheers, Neale.>

Re: Brain damaged Flowerhorn? 7/2/09 Flowerhorn With Columnaris He has been improving greatly, taking pellets, then this am I see this.. I cannot find anything on your site and don't think it is columnaris but I thought I would ask you. What is it and what med should I use? <In a hospital tank, I would treat with an antibiotic like Nitrofurazone or Erythromycin type of antibiotics. The little white columns are actually a characteristic of columnaris.-Chuck> Re: Brain damaged Flowerhorn? 7/2/09 Indication of Columnaris Is it the larger white spot with the surrounding red or the flaking white spiky things that indicate columnaris? (for my forums understanding as I have posted pics) Thank you again so much. Lisa < The spiky white things are columnaris. The big hole could be hole in the head /trauma/or a bacterial infection. Treat with the antibiotics as recommended. Get the nitrates down to under 20 ppm with water changes and gravel vacuuming.-Chuck>

TB?   6/26/09 Hello, I've attached a photo ( sorry about the quality but I believe it shows what I am talking about) of my Rasbora trilineata. I have had him for 1 month and slowly I have noticed his spine in the caudal region has become bent. Until now I believed it to be a birth defect that merely became more noticeable as he grew. <Indeed. Well, it's untreatable but unlikely to spread, so would remove/euthanise this fish, but otherwise not worry over-much. http://www.wetwebmedia.com/euthanasia.htm > I have "trained" the fish to eat when I signal them so I can observe them eat. For the past 3 days he has stopped eating even though he comes when I signal, he does not eat. I have moved him into a quarantine tank to isolate. He was in my 90 gallon tank with 5 neon tetras and 2 other Rasbora trilineata. All added without quarantine as they were held in the same tank together at the store for me for one month while my tank fully finished off cycling ( I don't add until Nitrates are low and or algae is present). Cycle was done using a fishless method with a grocery store bought and rinsed shrimp in a rinsed stocking. I did not know fish could carry TB until I came across a FAQ by Don and I am alarmed by the symptoms similarities. <Fish TB is actually extremely rare, particularly among freshwater fish. The vast majority of bacterial infections of fish are opportunistic, meaning that they're caused by otherwise-harmless bacteria in the aquarium that are *allowed* to cause disease because the aquarist isn't doing something right in terms of water quality, diet, or whatever.> While his trunk does not appear to be swollen compared to the others his sudden loss of appetite and elusiveness are setting off alarms. If the most prudent plan of action would be to put down the animals, what is the most humane way to do this and also to dispose of the bodies without contaminating anything else. If this does not seem to be TB what are my next steps. Ammonia and Nitrite are 0 and Nitrate is 10 ppm. Lush bright green algae on sides and back. I do 30 gallon water changes once a week. Filtered with Aquaclear 110. The substrate is Eco-Complete plant substrate one inch thick across entire bottom. Temp 76F pH 7. Two Maxi-Jet 1200's for water movement. One bubble wand for oxygen. No Co2 injection. For lighting I use Corallife 96 watt 6700k bulbs. Quarantine tank is a 12 gallon nano cube that has been stripped down to have a sponge filter and is cycled. <The tank sounds fine. In this case, I simply think you were unlucky, and whether this fish has a birth defect, a viral disease, or some type of obscure bacterial infection, I honestly don't think the other fish are at major risk. So I'd certainly euthanise him (if he's not eating, he's not going to get better) and then simply observe the other fish to see what happens.> Long term plan for this tank is heavily planted without co2 only using common low light plants. Any advice is welcome I work with the public and can not risk carrying/having/spreading TB. <While Fish TB certainly exists, it's very uncommon. I'm not a medical practitioner, so if you need public health advice, I have to recommend you consult a qualified MD or vet. But in general, fish tanks are not a major health risk, hence their wide use is hospitals, waiting rooms, shops, sushi bars and the like.> Thank you in advance. <Cheers, Neale.>

Re: TB?   6/26/09 Neale, Thank you so much for your advice. I think I will take the fish to a vet to be euthanized and possibly get them to run some tests on it to make 100% sure. <Hmm... would sooner you euthanised the fish yourself: I wouldn't trust the average aquarium shop to make an effort to euthanise the fish humanely; most simply feed sick fish to any predatory fish or turtles they have in stock.> Although I no longer believe TB is an issue I figure it can not hurt to make certain. I feed TetraColor tropical flakes by Tetra and have decided to include frozen bloodworms to mix up the nutrition values. <Good. While a good quality flake like Tetra Min should be perfect, adding variety is always a good thing. I'd tend to recommend against colour-enhancing foods as a staple; indeed, unless you have red fish, they will have little/no impact on colours at all, and they don't do anything that crustaceans such as daphnia won't do just as well. Carotene is carotene, wherever it comes from...> While I have your ear I would like to run a short stock list to be added no sooner then a month from now. Hopefully then I will be sure there are no pathogens, odd chemistry or poor nutrition taking place in this tank. I want to add in this order. 3 Crossocheilus siamensis 3 (possibly more) Corydoras panda 5 Gasteropelecus sternicla <All fine, though Gasteropelecus are flighty and prone to throwing themselves at the hood if kept with boisterous fish or tanks without floating plants.> Do you think the TSAE will stress the hatchets out too much? <Depends how deep the tank is; if the tank is something over 50 cm in depth, I'd expect that the two fish would barely meet, since Crossocheilus tend to stay at the middle to lower levels. But if the tank is very shallow, say 30 cm, then you might have problems. Boosting the number of Hatchets would make a big positive impact: they're a lot more reliable in swarms of ten or more.> My tank is covered with eggcrate but I still don't want them freaking out. <Floating plants help.> I am unsure of what will come after but I believe I am pushing the stocking limit of my tank. They will be added in family groups as to keep the load on my quarantine tank low. Also how long should I allow my quarantine tank to sit fallow before I can quarantine more fish? In closing I have to thank all of you for the knowledge that has accumulated on this site. Neale has helped me with other tanks in the past that have absolutely flourished. Another invaluable article on tap water preparation, storing and polyvinyl has saved me oodles of money/livestock. I have even earned a free True Siamese Algae eater through helping my LFS separate their Flying Foxes, False Siamese Algae Eaters and their True. Much of my success I owe to this site. I wish I could remember all the authors of the various articles I have read that have made me very skilled at aquatic husbandry. <Thanks for your kind words!> Also I would like to urge my fellow aquarist to get out there and shop the local mom and pop fish stores. They do not seem to be doing well with the economy, mega store and online competitors. <All very true. But ultimately it does depend on the Mom & Pop store being at least reasonably decent; too many of them had dingy tanks, limited selections of fish, and questionable husbandry practises. Competition is a good thing, and those family stores that can meet the demands of modern aquarists can do rather well, particularly if they gear themselves up to providing "value added" services such as setting up tanks in offices and shops (a real money earner!) or visit aquarists at their homes to help with marine and jumbo freshwater tanks that can cause problems to less experienced hobbyists.> Thank you! <Cheers, Neale.>

Saprolegnia on shark (RMF, second opinion?) <<Nada to add>> 4/26/09 Hi crew! Please help me! I am trying desperately to save my iridescent shark. <Yes, I can see from the photos he's in a bad way. A very difficult species to maintain, and I fear the problem here is more about his environment than anything else. Iridescent Sharks are food fish, and they simply don't do well in home aquaria. While they can be kept in aquaria if you have lots of space, 55 gallons isn't enough. Moreover, they are difficult fish to mix with other species. Despite their size, they are super-nervous, and perhaps surprisingly, should be kept in schools of 3 or more specimens.> He is 5 years old. Was staying in an established 5 year old tank, 55 gallon, with two kissing Gourami and a Pleco. Don't exactly know how he got hurt, maybe fight with Pleco that is a foot long. <Not so much a fight, but I do wonder if [a] the Iridescent Shark bruised himself or otherwise develop a light infection; and then [b] the Plec took advantage of this and started rasping away at the infected tissue. Plecs are notorious for "latching" onto injured, moribund or otherwise slow-moving fish that are exuding blood or mucous into the water. While I'm not 100% sure, this is my guess here.> My shark is 10 inches. <Way too big for this aquarium. Even if the Plec exacerbated the situation, the primary cause of the wound or infection was surely some combination of water quality and/or physical damage, e.g., jumping into the hood or bumping into ornaments. Heater burns are another common cause of mortality and injury among catfish.> The next day noticed the patch of cottony fungus, identified as saprolegnia. I set up a10 gallon hospital tank at 80 degrees. <Can't possibly keep this fish in 10 gallons. I'm surprised it even FITS into a 10 gallon tank!> I treated water with 1 tsp water conditioner (Jungle Start Right with Allantoin, a skin protectant), 1 tsp of Wardley Ick Away (malachite green), 1 tsp. of Melafix and 1 tsp of Jungle Fungus Clear Tank Buddies (Nitrofurazone, Furazolidone, potassium dichromate). <Random medicating is usually not a good idea. Remember, while Fungus isn't especially difficult to treat, it's a secondary infection that results from poor water conditions and injury. In a case like this, you need the fish to be in optimal water conditions, and even on his own, 55 gallons would barely provide that, let along 10. You also need to treat with something very specific for severe fungal infections; I'd recommend something along the lines of Seachem KanaPlex. Melafix is useless once fungal infections are established (I'll allow it might have some preventative value) and Ick medication is clearly irrelevant.> The only other items in the tank are the heater and an air stone. I have been feeding him Jungle Anti-Bacteria Medicated Fish Food, but he does not seem to be eating anything. <Don't feed him at all until he's in a tank offering optimal water conditions: 0 ammonia, 0 nitrite, low nitrate, pH stable around 6.5-7.5, and moderate hardness.> I clean up the food that he does not eat each morning. His eyes are clouded over, maybe he can't find his food. <Not a good sign; usually implies (if both eyes are cloudy) some type of secondary bacterial infection. Again, KanaPlex should help.> He has been in this treatment for 5 days, with no improvement, seems worse. His body is almost completely covered now.. I am sending you pictures. When will this treatment start to help? <No.> Or am I doing something wrong? <Yes.> Please help me! <Done my best. While I've seen fish come back from worse (they really are amazing sometimes) this does depend on optimal environmental conditions, which I fear you're not providing. Seriously, this is a fish that needs a tank twice the size of what you have, if not more, and a whopping filter with massive water turnover and plenty of supplemental aeration. Iridescent Sharks are classic riverine fish with little tolerance for stagnant water. Adults are routinely 60-70 cm long under aquarium conditions, and wild specimens twice that, weighing about the same as a family dog. Big fish. Cheers, Neale.>

Establishing an optimum bacterial population – 4/17/09
Dear Crew
<Hello,>
I have a question about establishing a bacterial culture in an aquarium.
<Not an issue; the bacterial population will expand and contract to the biomass of fish in the tank. The only limiting factors are oxygen availability and physical space, the two issues that determine whether a filter is adequate for the task. More flow = more oxygen, and more media = more physical space.>
Long, long ago (in the 1970s) I was taught that an aquarium performs best if it goes through a crisis, in the sense that it undergoes a large bioload early in its life.
<Yes and no; the filter bacteria population grows precisely at the rate determined by the oxygen availability, the physical space for them to inhabit, the availability of ammonia/nitrite, the temperature, and the pH. If you have a lot of ammonia early on, yes, the bacterial population can grow rapidly compared to an otherwise identical tank with less ammonia. But unless that high ammonia concentration is maintained, the population will quickly die back to a small population maintained with less ammonia. They don't "hibernate" in any meaningful sense waiting for ammonia spikes weeks or months apart. Hence, you need to cycle a filter with an ammonia source equivalent to the biomass of the fish being added, and when you do add further fish on top of that amount, you add them in small, spaced apart batches so the bacteria population can multiply upwards.>
To achieve this, when setting up a new aquarium I would get the filters running, add some bacteria (usually sand from an established tank), and throw in a few dead shrimps or a piece of fish fillet.
<As good a way as any.>
There would be no inhabitants in the tank except the bacteria. Over the ensuing weeks, the meat would rot, the tank would stink, and when the cycling process was finished, I’d do a large water change.
<Yep.>
The thinking behind this was that if you caused a crisis like this, with a massive ammonia spike early in the piece, you would establish colonies of bacteria in the filtering system that were at the maximum potential that could be achieved.
<Sort of; what you're doing is creating a source of ammonia equivalent to however much food you'd add if there was a fish in that tank. It doesn't matter to the bacteria whether the ammonia comes directly from a shrimp rotting on the sand or else a shrimp that passed through the gut of a fish. Ammonia is ammonia is ammonia. But, here's the thing: the art is in waiting for the ammonia to drop to a safe level, and then adding a fish or two to keep "topping up" that ammonia for those bacteria in the filter. Consider an extreme example: say you waited three months. The ammonia produced by the shrimp will have been all used up by then, and the bacteria in the filter would have died back to some minimal value. Likely not zero, because there'd be algae and other micro-organisms in the aquarium, so there'd be some small amount of ammonia, but nothing like as much as if there'd been a school of Guppies.>
The idea was that this optimum population of bacteria would occupy all the available sites in the system, and they would work at nitrification as need arose.
<There's no "optimum" level you can build into a system; the bacteria numbers will be limited by whatever is in least supply. This is called the Law of Limiting Factors and affects numerous biological systems. If ammonia is at a low level because a fish tank is empty, it doesn't matter how big the filter is, or how optimal the pH, or how perfect the temperature -- the bacteria population will be small.>
In other words, if you had a small bioload in the tank, the bacteria numbers would remain constant but they would have to work less.
<No. Allowing for a certain lag for the bacteria to die back, the population would be exactly proportional to whatever is in least supply.>
If you gradually increased the bioload to the maximum appropriate for the size of the tank, the bacteria would adjust their metabolism and work harder to cause nitrification. It was thought that the population of bacteria would remain constant, with fluctuations in activity depending on the bioload.
<Not sure they adjust their metabolism; rather, you have X bacteria, or 10X, or a 100X bacteria, depending on how much of whatever limiting factor is available.>
The concurrent idea was that if you didn’t cause a big crisis, but cycled the tank by only placing in it a few hardy fish, the bacterial population would establish only to meet that bioload, and the colonies in the filters would not be as dense as it would have been if you’d gone the ‘full crisis’ way.
<Yes, when you cycle with, say, 4 Guppies, you get sufficient bacteria in the filter to consume the ammonia produced by 4 Guppies; no more and no less.>
In other words, there would be less bacteria by using the slow method.
<No, you get precisely the same. All depends on the limiting factor.>
It was thought that this would constitute the bacterial population for the life of the aquarium and that the numbers of bacteria would not increase when you increased the bioload – the bacteria would simply work harder to handle nitrification, and the system would never be as capable of handling a large bioload or a crisis in the way that a ‘full crisis’ system would..
<No; what limits the bacteria population isn't how you created the tank, but what the conditions are at the moment. Double the amount of ammonia in any aquarium and the bacterial population will (within a certain period of time) double as well (assuming other factors, such as oxygen or physical space, aren't limiting).
Therefore, it was taken for granted that, if you wanted an aquarium to have its full potential for nitrification, the ‘full crisis’ method was the way to go.
<No.>
Now, this may be ‘old’ thinking, and I’d be glad if you would comment on what current thinking is. I’m setting up a large freshwater system that will eventually be heavily stocked, and I’m debating whether to go with the ‘slow’ method with a few fish or to use the fishless ammonia method to cause an initial spike in the hope that it will give me better long-term results. Is there an advantage of one method over the other?
<Absolutely no advantage to creating a "crisis" if you don't follow it up with an equal amount of ammonia day-in, day-out. If you add some shrimp and the ammonia concentration goes to, let's say, 10 mg/l, but then two weeks later has dropped to 1 mg/l, then the number of filter bacteria in that aquarium will be precisely the same as an aquarium given 1 mg/l every single day. Biological systems are ALWAYS limited by whatever is in least supply at the time, and NEVER expand to the potential of what might have been there in the past or might happen again in the future.>
I’m sorry this is so wordy.
Les (Australia)
<Hope this helps, Neale.>

Re: Establishing an optimum bacterial population  4/18/09
Neale, that helps more than you can imagine. Many thanks for this most comprehensive collection of information. That has settled years of wondering for me. At last I can approach what I'm doing in an informed way.
Best regards to you.
Les
<G'day Les. Happy to have helped. Good luck cycling your new tanks, however you choose to do it! Cheers, Neale.>

Mollies with Columnaris and Ich – 03/22/09
Hello Crew,
<Hello Carla,>
I'm in a bit of a quandary. I purchased three mollies the day before yesterday, and placed them in my cycled 10 gallon quarantine tank (pH: 8.1, ammonia: 0, nitrites: 0, nitrates: 0 -- I had a bunch of extra cuttings so
the tank is stuffed with live plants).
<Mollies don't do well in small tanks. They're very sensitive to nitrate as well as ammonia/nitrite, and in small tanks it is very difficult to keep them healthy for long. Minimum tank size for small Mollies (Shortfin
mollies, black mollies, balloon mollies) is 20+ gallons, while large Mollies (Sailfin mollies, liberty mollies) is over 30 gallons.>
Unfortunately yesterday I observed that one of the mollies had what we used to call cotton mouth or mouth fungus.
<Very common with Mollies, especially when kept in freshwater conditions.>
I understand, from researching your site, that this is likely Columnaris (bacterial).
<Indeed. You will need a suitable antibiotic or antibacterial (as opposed to a make-believe solution such as tea-tree oil or salt.>
Today I also observed two Ich spots (sure glad I quarantined). I was going to go the salt + heat route, but I learned (also from researching your site), that Columnaris grows faster with higher heat.
<Your options are limited here, but in this case, I'd raise the salinity to deal with the Ick, and treat with an antibiotic/antibacterial at the same time. Since Mollies are best kept at SG 1.003, I'd recommend 6 grammes of marine salt mix per litre of water. There's not much point trying to keep Mollies in a freshwater aquarium because they rarely (seemingly, less than 50% of the time) do well. You're also fighting with one hand behind your back because the tank is so small, so a difficult job is being made twice as hard.>
My questions are: Should I raise the heat, and how I can treat both the Columnaris and Ich concurrently? Also, should I remove my plants?
<Plants will not be affected by antibiotics or antibacterials used correctly, and a salinity of SG 1.003 is fine for hardy, salt-tolerant plants.>
Thanks very much for your help and your wonderful website.
Carla
<Cheers, Neale.>

Re: Mollies with Columnaris and Ich   3/23/09
Thanks very much for your help. The Mollies are currently in a ten gallon tank because they are in quarantine (their permanent home will be a 40-gallon heavily-planted breeder tank).
<Ah, that makes sense. A 40-gallon system will be perfect.>
The water parameters of that tank are:
Ammonia: 0
Nitrite: 0
Nitrate: 0
pH: 8.2
Carbonate hardness: approximately 200 mg/L CaCO3
<That's 200/17.8 = 11.2 degrees KH. That's extremely high, and while perfect for Mbuna or Central American livebearers, a lot of other fish will find that a bit on the hard side for their tastes. Do be aware when choosing fish and plants.>
Their tankmates will be Wrestling Halfbeaks, Scarlet Badis, White Clouds, and Threadfin Rainbows.
<Halfbeaks will thrive, the others should tolerate, but may not show optimal colours or longevity.>
I was hoping the Mollies would do well without salt because of the high pH and hardness, and I wasn't sure (aside from the Halfbeaks) whether the plants and other residents would appreciate the salt.
<Plants that tolerate hard water generally do well in slightly brackish water too; species such as Vallisneria, Hygrophila, Java ferns, hardy Crypts, etc. If you have plants that need soft water, chances are they
aren't going to thrive a this level of carbonate hardness either, so it's a moot point. As for the fish: Halfbeaks tolerate salt well, but the others are truly freshwater fish.>
But I will add salt and remove some of the other residents and non-salt tolerant plants if necessary.
<Would be my recommendation. Mollies deserve a tank of their own: they're spectacular fish, and wonderful pets. But they are finicky in freshwater systems. They need perfect water quality. You might decide to medicate them in the quarantine tank, and when they're healthy again, try them out in a plain freshwater tank. With luck, you'll be okay. But if you find you're constantly having to deal with Fungus and Finrot, remove the Minnows, Rainbows and Badis, add a little salt, and maintain the system at SG 1.002-1.003.>
I've started to slowly raise the salinity of the quarantine tank, and I'm off to the LFS to pick up the antibiotic and a hydrometer. I believe we have Maracyn and Maracyn II available here (Canada), so I will purchase
both.
<Cool.>
A couple more questions, if you'll bear with me:
<Of course.>
Which Maracyn product would be most effective against Columnaris?
<Maracyn rather than Maracyn 2 is usually used first. It contains Erythromycin, which should work on Flexibacter columnaris.>
If the Mollies recover, when would it be safe to place them into my main tank (so that Columnaris does not contaminate that tank).
<Columnaris, like Finrot, is a disease latent in all tanks, and the bacteria involved is presumably harmless most of the time. It appears not because a fish "caught" the disease, but because the fish was somehow
weakened, and its immune system overwhelmed. So provided the other fish are healthy, you shouldn't worry about cross-contamination.>
Thanks again...
<No probs.>
Carla
<Cheers, Neale.>

Re: Mollies with Columnaris and Ich - Update 04/03/09
Thanks very much, Neale, for your advice. Just thought I would give you an update on the Mollies. I used the salt + heat treatment for the ick, and the ick has disappeared.
<Good.>
For the mouth rot, I couldn't find Maracyn at my LFS, so I used TC capsules (tetracycline). The mouth rot hung around during the course of the treatment (5 days), and then I had an ammonia spike (the packaging on the TC capsules claims that they will not affect the biological filter, but I suspect otherwise).
<Oh dear.>
Unfortunately one of the Mollies died (oddly, it was the healthiest, dominant female).
<Sorry to hear that; I wonder why?>
I subsequently performed 75% water changes for the next several days to control the ammonia, used activated carbon to remove the tetracycline, then added some nice filthy filter media from my other tank to repopulate the nitrifying bacteria. Over the next several days, the mouth rot on the remaining Mollies disappeared, but I'm not sure if I can attribute it to the tetracycline or the water changes.
<It's a combination: the antibiotic kills off the bacteria, but improved water quality allows the fish's immune system to repair the damage and prevent re-infection>
Anyway, the remaining Mollies have recovered, and in a week or so, I will remove them from quarantine and place them in my 40-gallon tank.
<Great.>
Also, you were right, the salt did not seem to affect my plants (Hygrophila polysperma, Hygrophila corymbosa, Rotala rotundifolia, Java Moss, and Bacopa monnieri).
<Not sure about Rotala, but certainly the others are happy in brackish water, let alone slightly salty/warm water of the sort used to treat Ick.>
Thanks again for your help,
Carla
<Thanks for the update, Neale.>