Re: 120 Reef Sump/Refugium 5/3/08
Hey Scott John again with another question. I want to start stocking my tank with rock. My question is Doctor Fosters & Smith have Fiji foundation rock I could get 140 lbs for $230.00. I would be adding some nice rock onto this to seed. They say it has some life on it.
<Yes, it is still a live rock, not a dry rock.>
What do you think about this?
<It is a super idea.>
Eventually it will all be live, right?
<It is already, just not to the point of having the aesthetic appeal of the higher quality rock you are putting on top.>
My second question is I don’t have my light yet. Would it be ok to have in tank while cycling with out any light it would be a few months before I get the light.
<You can, but all your rock will end up looking like the base rock. You will be better off getting the light first.>
Running low on funds.
<The constant plight of the reefkeeper!>
Or should I put this toward the expense of the light then add a little rock at a time after I get the light?
<This is what I would do my friend. Scott V.>

Play Sand in Refugium DSB? – 04/26/08
Hello Crew,
<<Howdy, Mark>>
I've been doing my homework on DSB's and substrate and I'm in the final stages of setting up a 90 gal tank.
<<Neat!>>
I modified the drain from 1 ¼ to 1 ½ and built a standpipe.
<<Excellent>>
I made a 3 compartment acrylic sump which will hold about 20 gal under normal op. I will have about 8 gal in a refugium and the skimmer compartment will house an Aqua C- EV120.
<<A good skimmer choice>>
The middle compartment holds the return pump and heater.
<<So the refugium and skimmer compartments are at the opposing ends? Interesting design…>>
I have a closed-loop on top of the tank with (4) ½" outlets to be hooked to a MAG18.
<<Mmm…considering headloss, you may want to consider the Mag24 (you need 350gph or more per nozzle “after” headloss)>>
Lighting will be 300 watts MH on the display and a small standard fluorescent on opposite photo cycle for the refugium. My question concerns the refugium and tank substrate. I plan on keeping corals in the future but will initially move the 50# of LR and the following critters from my 55 to the new tank:
2 False Percula
1 6-Line Wrasse
2 Yellow Damsels (these guys are diggers) may give them back to LFS
1 Coral Beauty
1 Sail Fin Tang (Zebrasoma veliferum)
<<Great fish…but needs/deserves a tank at least three-times larger than the 90g, my friend>>
1 Peppermint Shrimp
1 Turbo Snail
1 Cortez Hermit
With this fish load I've read that a DSB in the main display may not be a good choice.
<<Can take up needed swimming space>>
I'm not very keen on the looks of a DSB in the main tank anyway.
<<I’m a huge fan of DSBs, but then I have a very large display tank…Bob pretty much always advocates a remote DSB>>
I'm reading that Aragonite is the better choice for substrate due to buffering capacity but that silicate based sands can work for a DSB.
<<Yes…I used such in my propagation system (is not “pretty” though)>>
Due to obvious cost issues with Aragonite coupled with the bio-load I'd like to put only ½" (approx 20-30# of the 1-2mm size) in my display and then use 4" of fine white play sand in my small refugium.
<<Mmm…if it is not “Aragonite” it will not be “white”>>
I don't want to use the sugar fine stuff in the display due to the closed-loop possibly causing a sand storm with only ½" of depth.
<<Can be controlled to some extent by controlling the direction of the nozzles…but understood>>
I mainly would like the benefits of nitrification with the DSB along with nutrient export utilizing macro algae in the refugium.
<<I see>>
I have read about the issues of diatom blooms associated with using silicate based play sand.
<<Generally short-lived as the sand will become “encapsulated” with bacteria>>
Some say it's not going to cause the problem but can exacerbate it.
<<Maybe so>>
Others say do not use this type sand at all.
<<Differing opinions>>
I've never incorporated either a refugium or DSB so this is all a new venture for me.
<<Both will be of great benefit>>
My current system has a wet/dry and H.O.T. skimmer. Wanted to get away from the wet/dry.
<<These are of use to FO and FOWLR systems due to their ability to rapidly adjust to fluctuating bio-loads, but reef systems are more sensitive to the elevated Nitrates associated re and are better off utilizing live rock/live sand only, with its capacity to metabolize said Nitrate>>
Do you see any major problems utilizing this kind of approach with my substrates?
<<Not at all>>
Are there any issues with the critters in the DSB with the use of said play sand in the refugium?
<<The play sand is more abrasive than Aragonite sand which can irritate some macro-organisms (e.g. – sand-sifting Gobies), but is of little concern to the majority of the substrate biota>>
Other thoughts ideas?
<<I say…give it a go>>
Thanks for the great site!
Mark Gustin
<<Happy to share. Eric Russell>>

Refugium and Filter Media 4/9/08
Hi guys,
<Walter.>
I have tried finding this question but can’t seem to find it.
<OK>
I have an 85 gallon tank with an overflow box and wet/ dry filter system. I also have a CPR protein skimmer. I have about 100 lbs. of live rock in the tank. I am trying to landscape the tank to make appealing to the eye as well as serve its purpose for the inhabitants. My questions are: Can I put some of the rock down in the sump of the wet/ dry filter and I have read that in a reef tank to take out the filter media that is in the trays of the wet dry. Thanks for all the help.
Walter
<You certainly can put some of your live rock down in the sump. It will serve a type of refugium. If you have the room consider lighting the area and adding some substrate with macroalgae. The filter media can be removed. It will accumulate detritus and contribute to nitrate problems. The live rock and skimmer will provide the filtration. I have included a link below for you regarding the refugium addition. Welcome, Scott V.>
http://wetwebmedia.com/refugium.htm

Refugiums, des./filter media  4/9/08
Hello again,
<Hi Shawn>
My question for today is, in my refugium after the water goes through the area with the live rock rubble, sand and algae it overflows into the chamber where the return pump is located. Where the water overflows is a piece of foam to catch debris coming out of that section. Does the foam prevent any critters that the refugium produces from entering the next area, hence not making it into the main tank. Should this foam be removed or will the plankton pass through the foam.
<I would remove the foam or at least replace with a coarse sponge to trap larger particles of waste. The plankton will then find their way (much more easily) into your tank and continue multiplying and providing food there.>
Thanks in advance,
<You're welcome. James (Salty Dog)>
Shawn

Combining Overflows/Refugium Substrates 2/26/08
Greetings WWM Crew,
<Hello Bart.>
I have always enjoyed the hours I have spent reading on your site and the valuable info you provide. For this I offer my thanks.
<Thank you.>
I have a few plumbing questions for you regarding a system project I am undertaking. After three years of successful reef keeping in my 72 gallon bow-front I have acquired a pre-drilled AGA 120 and am making the switch. I am especially excited to do away with my siphon overflow (no major mishaps...Just lucky I guess).
<I hear you my friend!>
I will keep a variety of LPS corals on about 120 lbs of liverock and stock fish very lightly.
The tank is pre-drilled with two Megaflow overflow chambers installed. They have the standard 1" drains with Durso standpipes and ¾" returns. I understand from my research here that these are smaller than is to be desired, but my thinking is that I can get healthy water flow if I add some big powerheads in the tank and take care of filtration and skimming in the sump with the 12 or 1300 GPH I will get from the twin drains. Is this reasonable to assume?
<I am sorry, but no. These are smaller than to be desired, a 1” bulkhead will only flow around 300 GPH safely, giving you around 600 GPH total draining capacity.>
My plan is to place a 50 gallon sump in the basement, directly below the tank. If I were to combine the two 1" drains into one 2" pipe, will my drains slow down?
<This will work fine, the 2” has about 4-5 times the draining capacity as a 1”.>
I'm thinking it would be easier to send one pipe through the floor than two. The sump will be a simple design and house a skimmer (not selected yet) followed in line by a refugium. The return pump will be an IWAKI MD70RLT which should be able to handle return flow approaching 1400 GPH at the required head.
<You will want to choose a smaller pump.>
Since the combined flow to the sump directly below the tank should be around 1200 GPH, would this be too much flow for a refugium housing only Chaetomorpha?
<No, that is fine for the Chaetomorpha, but you will not be flowing this much.>
I am considering a sump with no substrate because I have heard that the substrate can become a nitrate factory. This is confusing because I have also heard that Deep Sand Beds are denitrifiers. What are your thoughts regarding refugiums without substrates?
<I like and use the DSB method. Substrate can become a nitrate factory when it traps excess detritus, usually a trait of large grain substrates. The use of fine substrates will not be an issue and will benefit your system with proper water flow, which you will need even if you leave the refugium bare bottom.>
My plan is that the Refugium and the skimmer would be the ONLY filtration in this tank.
<And the live rock in your display.>
I thank you in advance for any help you can offer. Keep up the good work!
Bart
<Welcome, will do. Scott V.>

Refugium DSB question
Getting To The Bottom of Things (Substrate Materials) 2/21/08
Hi Crew,
<Hey there! Scott F. in tonight!>
I have chosen to go with a DSB (depth around 5'')?using sand for my new refugium. I'm looking at 2 different types. Both being of the Caribsea brand. The first one is Caribsea Aragamax sand 0.2 - 1.2mm.The ad for it says "Known as oolitic sand grade is ideal for shallower beds allowing denitrification in as little 1" in depth." The other I'm looking at is Caribbean Sea Aragamax select 30lb 0.5-1.02 . The ad says "Provides nitrate reduction in shallower beds and also has an increase in pore water space which allows maximum diffusion rates of minerals and trace elements." I was just wondering if you have an opinion on which one is better, or if there is combinations of sand that is best. The main reason for my fuge is filtration, denitrification, and making my take more self sufficient.
<I have used both products, and I would recommend either.>
Also, Caribsea has a line of product called Ocean Direct. It's suppose to be live sand with true beneficial bacteria. Could this be helpful to seed either of the above two substrates??? The ad says nothing about the diameter of the grain size though. Would it be bad to mix in a little of the ocean direct being that it probably has a completely different grain diameter??? I'm also? going to seed with live rock fragments and I would to like to get some sand from an existing system but I don't know if that is going to be possible? Any information will be appreciated. Thank you in advance! Peter
<Well, Peter, I've used the live stuff, too, mainly because the particular sand that I wanted was only available "live". It does contain some bacteria, but it certainly does not contain the beneficial micro and microfauna that you'll want. I would still use a variety of substrate materials, including bits of rubble and sand from a healthy, established reef system, to help seed the system. In my opinion, you can't have too much diversity in a sandbed! I see no great disadvantages in mixing a few different sizes of fine substrate together. Should be just fine! Best of luck to you! Regards, Scott F.>

Sump/Refugium Set Up and Substrate 2/9/08
Hello Crew
<Hello Peter.>
I have to once again start out by saying thank you for the great site! Ok, my project is coming to an end. I have built my refugium- basically an identical knock off to aqua-fuge pro only a little bigger 45 to 50 gallons capacity. It will be supporting my 250 gallon fish only system.
<OK>
The first chamber is going to house a G series ASM protein skimmer. I have a 65w 6700k compact light. In the beginning, I plan on using the bio balls that are in my wet/dry now to fill the first chamber (w/protein skimmer) and last chamber with return pump. Over time I will replace first chambers bio-balls with live rock. I have already taken out some of the bio balls in the wet/dry cleaned them and placed them in the over flow in hopes that this will also help support the system during conversion period.
<This will help somewhat, although they will not be getting the true wet/dry super oxygenation effect.>
My questions are:
1) I am still on the fence on the subject of substrate for the fuge. My choices are fine oolitic sand about 5 inches, Mineral Mud, Miracle Mud, or Kent bio-sediment. The Main purpose of my refugium is filtration (one being bio-filtration) and making my tank more self sufficient.
<There are many opinions on which is best, my vote is for the oolitic sand in the depth mentioned. It is more cost effective, easier to use in my opinion and works just fine.>
2) I would like to reduce nitrates. I know a DSB with fine oolitic sand works well for this but will this also be achieved if I use a DSB of about 5 inches with some Mud on the bottom and find sand on top or mixed together?
<Yes, you will still see the effects of a DSB here. You can certainly mix substrates if you wish.>
Should there be more sand then mud or mud then sand?
<This is personal choice here. 100% of either or any combo in between can serve your purpose here.>
Can Nitrate reduction be achieved with deep mud alone?
<Yes, the same principles are involved.>
3) If I use the sand do you suggest buying it live?
<At least enough to seed the sand bed, better yet borrow some from an existing system if you can. Do be aware that true live sand is more than the water packed stuff in a plastic bag you see at the LFS.>
4) For my macro I am thinking Chaetomorpha. Any other suggestions for my intentions or does this sound good?
<This is by far my favorite macroalgae.>
Can I mix? For example, Chaetomorpha and mangroves?
<Mangroves will be fine to add if you wish, but I would not mix macroalgae, one will outcompete the other.>
5) Clean-up crew question. What organisms do you suggest adding to my fuge and when should I do this?
<Nassarius snails, when the tank and rock is cycled/cured completely.>
6) How do my plans with the bio-balls and live rock in chamber with protein skimmer sound is this a good place to fill live rock? It’s a pretty big chamber because the ASM skimmer.
<If you have the room I say go for it. Are there plans for any of the rock in the main display?>
7) Is there any harm in leaving the bioballs in the overflow after conversion period?
<Just the typical detritus accumulation/nitrate production associated with their use.>
8) Am I missing anything that can help my situation?
<No, sounds good.>
Once again thank you for your time. I just want to make sure I do this right the first time.
Regards
Peter
<Have fun with this project. I included a few links to help guide you here, there are many ways to do what you propose. Scott V.>
http://wetwebmedia.com/refugdsbfaqs.htm
http://www.wetwebmedia.com/livesand.htm

Deep sand beds? Depth... refugium...   2/8/08
Hi, Jake Smith here
<Hello Jake!>
My main tank is a 30 gallon and I have about 1 inches of sand.
I am setting up a refugium, and I was planning on growing some Caulerpa (I think that's how it is spelled) and other plants
The refugium is a 5.5 gallon tank and I put 20 pounds of live sand. so far the sand is about 2.75 inches deep. I was wondering if that sand bed would be at all beneficial or if I need to add more sand.
<I think you are fine with close to a 3" deep sand bed. This is deep enough for denitrification to occur. Your system is relatively small and should receive frequent weekly water changes of say 5 gallons per week to help maintain water quality and export nutrients.>
I Have heard that deep sand beds can cause problems. but seeing as in my refugium I am planning on having one fish, I do not think detritus will be a problem.
So basically what I was wondering is how deep of a sand bed would be the best depth and the least risky of detritus and ph drop and such.
<I am not sure I would add a fish to a 5.5gallon refugium and rather would keep any fish in the main display. You could add an invert to the refugium like a pistol shrimp and some Nassarius snails.
As far as problems with maintenance of deep sand beds goes, they are usually associated with elevated levels of phosphates and nitrates. Water changes will help reduce this problem from happening. The addition of a small fluidized bed reactor like the "POLY-REACTOR" by Via Aqua which comes with it's own pump would be a benefit to your system for the use of activated carbon and phosphate resins to help maintain water quality.
Finally, make sure that you are using RO/DI (Reverse Osmosis/De-ionized Water) for all of your water needs as this will help with maintaining a beautiful tank. Hope this helps-Rich...aka...Mr. Firemouth>
Thanks for all your guys help

Question about refugium sand bed 02/08/2008
Hi, Jake Smith here
<<Hello, Andrew here>>
My main tank is a 30 gallon and I have about 1 inches of sand.
I am setting up a refugium, and I was planning on growing some Caulerpa (I think that's how it is spelled)<<Caulerpa>> and other plants.
The refugium is a 5.5 gallon tank and I put 20 pounds of live sand. so far the sand is about 2.75 inches deep. I was wondering if that sand bed would be at all beneficial or if I need to add more sand.
<<Bump this up to about 4 inches for better use>>
I Have heard that deep sand beds can cause problems, but seeing as in my refugium I am planning on having one fish, I do not think detritus will be a problem.
<<DSB's don't necessarily cause problems. Incorrect setup DSB's cause problems in my opinion>>
So basically what I was wondering is how deep of a sand bed would be the best depth and the least risky of detritus and ph drop and such.
<<Shoot for around 4 inches minimum>>
Thanks for all your guys help
<<Thanks for the questions. A Nixon>>

Tank upgrade Substrate/Refugium 2/4/08
Hello, I would like to start by thanking you all for volunteering your time to run WWM! I am an avid reader, and deeply appreciate this resource.
<Thank you, it is a pleasure to be a part of.>
I will soon be upgrading from a 55 gallon FOWLR to a 75 gallon. My current inhabitants are a 5 “ Tetraodon nigroviridis, one 2 “Amphiprion clarkii, and one 1 1/2” Chrysiptera parasema. I don’t plan on adding anymore livestock after the move, I’d just like them to have more room to roam.
<Yes.>
This system has been running for about 2 years. When I set up the new tank, I will be adding more live sand and I was wondering which one to add first, the newly purchased, or the sand from my current set up?
<I would put the old sand on top or even just mix the two together.>
Right now the depth of the sand is about 2” but I’d like to increase that to 3” or 4”.
<Go for the 4” depth.>
I am guessing it doesn’t matter, but I really want to do this the right way and not cause a major upset that I could avoid. I also have an Aqua-Clear 150 that I’d like to stop using after I switch. I currently have about 40# of LR (will add more) and an AquaC-Remora Pro skimmer. I haven’t gotten rid of the Aqua-Clear because every time I perform maintenance, there are tons of micro crustaceans, etc. that have made their home in the filter and I think they must be beneficial.
<Acting as a small refugium.>
Would there be a benefit to adding a hang on refugium in place of the Aqua-Clear even though I am not going to be keeping inverts?
<Yes, especially if you grow macroalgae for nutrient export.>
I was thinking I could put some of the filter media in the fuge to entice the critters to switch homes. I know some advocate the removal of filters and some still find them useful, so I’m confused about my options.
<Possibly opt for additional live rock here instead. If you can divide the area with baffles and light it and add macroalgae this will be even better.>
I searched through the tank upgrade FAQ’s and didn’t see anything that pertains to the sand question, so any help would be appreciated. Thanks again! Jenny
<Welcome, good luck, Scott V.>

Replacing Old Sand Bed in Refugium 12/27/07
Hello,
<Hi>
I am planning on changing out my old sand bed (5yrs) for a new one and have a concern that this would cause my tank to start a cycle.
<Yes most likely, at least to some degree.>
I have a 180g SPS tank with a 40g refugium and a 20g sump, there is 250 pounds of live rock in display and another 50 in the refugium. Do you think taking the refugium offline and changing the sand (about 60 pounds) then putting it back inline would cause harm to my inhabitants.
<May see a ammonia/nitrite spike as the bacteria inhabiting the old sand bed is removed.>
As far as equipment I run a Deltec 851 skimmer , Deltec reactor with Rowaphos and a Deltec calcium reactor. I just want to make sure I do not crash the tank.
<Unlikely, I would guess the existing bacterial population will quickly increase to make up for the removed sand bed. Within a few days I would guess you will be back to normal.>
Thanks
Mike Winston
<Welcome>
<Chris>

Re: Replacing Old Sand Bed in Refugium 12/27/07
Thanks, would it help to add the top 2 inches of my existing bed to the new sand?
<Yes in that it would add back some bacteria and micro-fauna, but you will probably still see a small cycle.>
<Chris>

Refugium For NNR? 9/17/07
Hi Crew,
<Hello Ian>
I have a 90 gallon FOWLR that is more or less fully stocked (Yellow Tang, Golden Butterfly, Flame Angel, 3 Firefish, False Perculas (2), male/female Lineatus Wrasse).
<I'd say a little overstocked.>
I've removed the bioballs from the sump and added an AquaC Urchin skimmer in its place. I'd also like to establish a DSB for my tank for NNR. The problem is my stand/sump is very limited with space, so I was looking at using something like the CPR in-tank refugium in the sump (but only for a DSB). The size of this is 7 3/4" x 4" x 7 1/2". I would use sugar-fine at a height of 4-5". Would a DSB of this size have much impact for NNR in this tank or is it worth skipping altogether?
<You would be much better off setting this up as a combo (DSB/Refugium). Go for a three inch sand bed and stock with some live rock rubble and Caulerpa. You will need a small nine watt PC fixture over the refugium, they are reasonably priced at most fish etailers.>
Thanks,
<You're welcome, James (Salty Dog)>
Ian

Refugium/DSB Depth 9/13/07
Hey Crew,
<Hey whoever you are.>
I am designing a refugium for my 110g mixed reef system. This will be a separate vessel apart from the sump. Goal is NNR, nutrient export, plankton generation along with growing all the other little fellows to feed the livestock in the display. Will probably put small pump in sump to feed the refugium and then gravity flow back into sump. I am intending to put in DSB. I have a rather small foot print that the refugium needs to set it... 24" x 24"... but have some height to work with. Typically I see recommendations for DSB of 4"-6". So my question is, can I just make the DSB deeper, say, 12" -18" deep? Will the same volume of substrate function the same regardless of how it is housed?
<Personally, I wouldn't go much deeper than 4". Anaerobic areas can/will develop. Read here and linked files above for more on this subject. http://www.wetwebmedia.com/deepsandbeds.htm James (Salty Dog)>

Refugium Follow-up   7/16/07
Thanks for the help, Scott. Much appreciated. Just two follow up questions if you don't mind.
<Ask away!>
1. Do you think I should add more live rock/reef rubble to the fuge?
<It really depends on your goals for your system. The rubble can serve as a colonization site for copepods or other cryptic organisms.>
2. I've seen a lot of talk about sand beds becoming "nutrient sinks" but I'm unclear on what, exactly, that means and whether I need to periodically stir the sand or leave it as is.
Thanks! Andy
<Well, Andy, the "nutrient sink" argument suggests that a sandbed becomes "saturated" with organic materials at some point and then begins to leach nasty stuff into the water column, degrading water quality. In my opinion and experience, with decent flow and overall good husbandry techniques, you should not have such issues in your system. For way more than could ever be posted here, do check in the WWM article archives and FAQs under "sandbeds", and you'll find lots of good information. Good luck! Regards, Scott F.>

Refugium Substrate Question   7/8/07
Crew,
I have scoured the 5,000,000 refugium substrate FAQs and either I'm missing the answer or it's not there, so I'm sending it your way.
I am setting up a 30 gallon refugium.
<cool>
My goal is to use macro (Chaetomorpha) for nutrient export and to also create a habitat for pods using aragonite.
<It doesn't necessarily have to be aragonite. Copepods and amphipods like niches, holes and surface area. The macro algae will provide some of this. Another thing you can do is add rubble. I also use eggcrate.>
I realize that pods will make their way to the fuge from my display (110g, 75 live rock), but I am going to add a few pieces of live rock to the fuge anyway.
<good idea>
So here's my question--what grain size do you recommend for the aragonite and how deep should it be? I have an extra 40lb bag of 1mm-4mm aragonite left over from when I set up my display. Should I shoot for something smaller and more consistent for pod growth?
<As far as copepods and amphipods go, the sand grain size doesn't matter so much. But if you also want lots of worms and other benthic critters, a smaller grain sand would probably be better (1mm or smaller). If you don't want to spend a lot of money on new sand, you can use silicate (i.e. masonry) sand.>
Gracias!
Andy
<De nada :)
Sara M.>

Chemical filtration placement question for a hang-on refugium   6/24/07
Good evening,
I first want to thank you for your site and all the great information, I don't know if I could have survived this hobby without it. My question is as follows: When adding chemical filtration, specifically Chemi-pure, where should I place it in a CPR hang on refugium/ skimmer unit. I just purchased Chemi-pure and had it in the compartment after the skimmer and now it seems that the Caulerpa in the refugium is turning white and breaking apart. I thought about putting it in front of the return portion of the unit,
<Mmm>
but I am fearful that the copepods and stuff that is supposed to leak into the main tank from the refugium wont.
<Not to worry re this...>
The only filtration I currently have is live rock and the CPR and would love to add the Chemical filtration, but the only option I have is to place it in the refugium. I used to use carbon in my Prizm and thought it really helped. I would therefore like to continue with the added filtration with my new set-up.
Thank you in advance for all of your help!!
Cory
<Somewhere in the filter flow path, though not blocking same... toward the exit, return, though most anywhere in this unit would be fine... I would only switch such a product out once a month... using two would be best, leaving one in while changing the oldest each interval. Bob Fenner>

New Refugium, Substrate Mud Vs. Sand  – 05/08/07
Hi gang !!
<What’s Up Bob?!>
I have a few questions for setting up a refugium for a 135 gallon fish/coral tank.
<Try me…>
The refugium will be in addition to my also using a separate large 30 gal sump with an ETSS Pro 800 downdraft skimmer.  
<Great, just make sure the skimmer is allowed to process water before the ‘fuge.>
I will be using a 50 gal refugium that is 36x18x18.  
<Awesome size!>
Is this large enough?
<Plenty, sounds great. Will make a HUGE difference as far as the aquariums stability by the added water volume alone.>
What are the minimum and maximum flow rates I should have going thru the refugium?
<Well I will note that people often do not have enough flow in their ‘fuges, some are dang near stagnant. Having said that, depends on the targeted algae in the fuge’ (if that’s what you aim to do with it.>
Should I use live sand or Miracle Mud in the refugium?
<Pros and Con’s to both. I recently had a very detailed discussion about this with one of our chat-forum members I will link you to it; http://wetwebfotos.com/talk/thread.jsp?forum=17&thread=42973&start=0&trange=15 .>
How deep of a layer should that sand or mud bed be?
<See the link my friend ^^ .>
And finally, how deep should the water be from the top of the sand/mud bed be? I'm told that a shallow layer of water is better than a deeper layer.
<As far as lighting yes, but in general the more volume (water/space) you can get out of it the better.>
Thank you for taking the time to answer these questions.
<Anytime, and please do see the link, it’s the LONG post about 5 posts down. It will the questions you posed re: mud vs. sand and how much.>
Bob Drews, Ft. Lauderdale, FL
<Adam Jackson in Southern, California.>

Refugium Causing Cyanobacteria and Nitrates?  3/28/07
Hi,
<Hello Brian>
Thanks, as always, for your great site!
<Welcome>
I have a 75 gallon tank (fish, live rock, 2 clams, 1 anemone, lots of snails & hermit crabs) with a CPR Aquatics AquaFuge Pro underneath.  The refugium has a DSB comprised of miracle mud, a cheaper type of generic miracle mud, and some coarse sand/crushed shells.
<Mmm, all mixed together? I would NOT do this>
  About two days after
I installed the refugium, I put in a big mat of Chaetomorpha (sp?) algae.  I ran the lighting 24/7
<Mmm... this algae is not able to "do" the light reactions of photosynthesis constantly... needs a daily dark phase...>
(I believe it's an 18w 10000k).  After about a week, the algae started to turn brown, then it started to come apart (small pieces were accumulating in the mesh between the main compartment of the refugium and the sump), then red slime started to grow on the algae, then the red slime spread throughout the refugium, then the algae almost disappeared entirely.  Now, the red slime is out of control in the refugium, the algae is almost gone, and the nitrates in the tank are at 40 ppm (they used to be stable under 10 ppm at all times).  What's going on?  Do I need to add some kind of critters down there to keep the slime under control and to keep the nitrates lower?
If so, sand-sifting stars, snails?
<Uhh... Please read here re Refugiums: http://wetwebmedia.com/marsetupindex2.htm
... and re-read my comments above. Bob Fenner>
Please help.
Thanks,
Brian

Small Refuge Setup for a Nano-Reef, subst. biota  3/27/07
Hello Bob ... greetings from Manila, Philippines.
<And to you my friend, from Hawai'i's Big Island>
I've spent many hours reading your FAQ's .. so much great information on your site.  Thank you.  I hope you'll have time to answer my questions.
<Will try>
I'm setting up a 20-gallon tank, first FOWLR then moving into SPS.  I plan to go skimmerless.  I'm planning on a 5.5-gallon refuge.
<Okay>
Given that I'm going skimmerless, do you think I at least need a 10-gallon refuge, or can I get away with 5.5-gallons?
<"The bigger the better"...>
Also given that it is a small tank, 14" tall, I'm planning the following: 2-inches Miracle Mud on the bottom, 4-inches sugar-fine sand, 2-inches crushed shell on top.
<Mmm, I encourage you to somehow partition the "Mud" from the calcareous substrates... maybe with Siliconed glass partitions.>
This leaves less than 5 inches for my water space/Chaeto.  Is this water space too small?
<Mmm, no. Not too small>
I know your a fan of DSB's, but with a small tank, is this deep enough to encourage denitrification?  Is this the correct order and depth?
<Yes and yes>
I've read about methane pockets that can occur in DSB's which crash systems.  Some people stir up sand to release any small forming gases.  Others feel that the sand should not be disturbed as it will interrupt the denitrification process (I think this is your stance).  If I choose not to disturb the sand, how will I deal with methane gas pockets?
<I would not disturb this sand bed>
Is it a good idea to have any other critters in my refuge: i.e. hermit crabs
<Mmm, no... are too predaceous>
for any detritus, or larger brittle stars for sand movement?
Regards,
Jason B
<I would leave these in if they were natural recruits... but otherwise just count on incidental recruiting of various invertebrate infauna from your live rock in the main tank here. Bob Fenner>

Re: Small Refuge Setup for a Nano-Reef  3/28/07
Bob, you're great! :)  Thanks for replying.  I have a reply to your reply.
> <Mmm, I encourage you to somehow partition the "Mud"
> from the calcareous substrates... maybe with
> Siliconed glass partitions.>
If I split the tank in two with a glass partition, one side would have 2-inch miracle mud on the bottom, and 6 inches of sand on top - the other side would have 4 inches of sand on the bottom, and 2 inches of crushed shell/rubble on top.  Does this sound good?
<Mmm, I'd add the larger shell/rubble right on top of the sand... the sand on the bottom, w/ or w/o a screen, the rubble on top. BobF>
Jason

10" Miracle Mud & 10-Gallon DSB/Refugium - 04/04/07
Hello Buddies...quiet night here in Makati, Philippines, I'm Jason.
<<Greetings Jason...EricR here again...and tis a beautiful 79-degree evening here in Columbia, SC as well>>
I'm constantly changing my DSB/refuge design after reading so much on your site - this will be for a 20 gallon nano-SPS (skimmerless) tank (not yet running).
<<I'm a huge fan of the DSB with macroalgae refugium methodology myself>>
I thought a 10 gallon tank (12 inches high) would be fine.
<<Thought about this myself in our earlier exchanges...not much volume to work with really>>
However, 12-inches isn't deep enough, so I think I will have a custom made tank, still roughly 10-12 gallons.
<<Mmm, do consider this...many public aquaria utilize refugiums of equal or greater volume than the displays they support>>
After reading many of your FAQs and suggestions, an 8-inch sand bed, 2-inch crushed coral on top.
<<Though it provides a differing habitat, the crushed coral is not "necessary">>
That's 10 inches so far.  I know a DSB can't be too deep, but will I still get the same effect if I have a total of 8 inches (6" for sand, and 2" for the crushed coral)?
<<Would be fine>>
I'll have an external pump on my main tank, pushing water up to my refuge thru a bulk head.
<<I do recall>>
I'll have the bulkhead 2-inches from the top (is this too low?) and 1.5 inches in diameter.
<<Is fine>>
So that's around 4-inches there.
<<Ok>>
Would 4-inches of water space be sufficient for Chaeto, or should this be deeper?
<<Is all relative...the lower water depth simply means "pruning" the Chaetomorpha more often to "fit" the space>>
So far, my running height of the tank would be 18-inches... That's gonna be taller than my main tank, and not exactly want I want displayed (since my refuge will also be shown, and not hidden).
<<The biota in the refugium can be every bit as interesting as that in the "display" tank>>
Can you guys help me shrink the size down ... while still having an effective DSB?
<<Reducing the DSB to 6-inches will still be effective...and give you a bit more room for the macroalgae>>
You guys also suggested that I could split the tank with a glass partition if I wanted to have some Miracle Mud... If I did that, I would have a 10" glass partition, one side to hold the sand/coral. the other to have 10" deep Miracle-Mud. is this wise? :) <<Might be worth the experimentation...but personally I wouldn't bother>>
Thank you guys :)
Jason
<<Always welcome, EricR>>

Mixed substrate in refugium/sump   1/27/07
I am in the process of setting up my new 75 gallon reef tank with a 37 gallon sump.  I am currently running Miracle Mud in the sump on my 65 gallon but want to use both a DSB and the Miracle Mud in my new setup.  Bob told me in an earlier email that is best to have separate chambers for the different substrates as opposed to layering them in one area.
<Yes, this is so>
My new sump is tall enough that I had to build a platform in the skimmer section of the sump to raise the skimmer to its optimal operating depth.  The platform consists of 6 PVC pipes cut 3 ½ inched long and glued to stand on end.
<With holes, notches... to allow some water movement within>
On top of this is a piece of egg crate material the size of the compartment that the skimmer will sit on.   Can I utilize the 11 x 16 x 3 ½ inches of space beneath the skimmer for my Miracle Mud?
<Mmm, yes>
The egg crate material would allow for water flow and I would spread a thin layer of sand on top of the mud to keep it in place and hold down on the silting.  The DSB could then go in the 14 x 16 x 18 inch space. Do you see this as a viable option?
<I do believe so>
Thanks for being there for us.
Mike
<Thank you for this follow-up. Bob Fenner>

One comment and two questions, Aqua-C, mud in a 'fuge and feeding Scler.    1/27/07
Hello WWM Crew,
<Bart/holomew!>
Thanks you so much for the wonderful service you provide.  I wanted to comment on the great service I received recently from one of your sponsors.  I love my Aqua-C skimmer!  The O-ring dried out and cracked (as O-rings do). I made one phone call, waited two days and TWO new O-rings arrived in the mail.  No muss, no fuss, and NO CHARGE!
<Hee heee, Freeeeeee!>
This is a great company and they will be skimming for me till I no longer need to skim.  Now, two quick questions if I may:  I am running a closed-loop return manifold that I constructed using Anthony's informative article on my 72 gallon bow-front reef system.  It was fun to build and works great with the old-style external Quiet-One pump that I have.  My question has to do with the intake.  I used my miter-saw to make cuts half-way through a ¾" piece of PVC to make a strainer.  Over this I have placed a coarse sponge filter to keep the tiny snails I have all over my tank from getting into the pump.
<Good design>
  I dislike the sponge filter because I have to clean it and because I suspect it is a source of nitrate in my tank.  It is the only mechanical filter I have on the system as I use a refugium and skimming for water treatment.  Do you think I could remove the sponge?
<Mmm, no, I'd leave it, or something similar in place... as a screen>
  Would the tiny snails be able to stop the pump?
<Possibly, yes... and/or cause trouble in being crushed, dissolving...>
Secondly, I have an assortment of Caulastrea and Euphyllia corals (widely spaced, of course).  Do you have a recommendation as to a food of the appropriate particle size for feeding these animals?
<A mix of live or frozen/defrosted zooplankters... "of small size", 1/16" diameter nominally will do>
I suspect the Mysis I feed the fish is a bit large for these corals to utilize.
<Yes, likely so>
Thanks again for the good work you do.
Best Regards,
Bart V
<Welcome... Oh and please do read here: http://wetwebmedia.com/faviidfdgfaqs.htm
and here: http://wetwebmedia.com/caryfdgfaqs.htm
Bob Fenner>

Unasked Refugium Questions? Around Here? Not Likely. - 1/24/07
Hi everyone,
<Hey Pam, JustinN with you tonight.>
back with another question, AND, I'll bet no one has asked this yet!!
<I'd honestly be a bit surprised -- it is kind of a rarity around these parts...>
I just set up my refugium (24X15X4) and added live aragonite and mineral mud.
The mud container says to let it sit for 3 days without powering up the refuge! Three days?!!!
Is this correct/ necessary?
<Depends how much the clouding of your aquarium would bother you. If you do not wait this duration, you will likely end up with a dusty-looking display.>
Also, the total depth of these additives will be about 5&1/2 inches. PLEASE, don't say this is too deep! I'll be adding a nice piece of Feather Caulerpa and some live rock.
Can't wait to hear from you!!
Thanks
Pam
<May I suggest foregoing Caulerpa sp. algaes, and instead, go with Chaetomorpha? The reason being, Caulerpa sp. run a risk of going sexual and infesting your aquarium to plague proportions, aside from not doing as good a job at nutrient removal as Chaetomorpha. Chaetomorpha does not go sexual, is easier to trim, provides a living space for numerous beneficial creatures, and will consume your wastes and phosphates faster to boot. The choice is yours, but do research this choice before you make it. Cheers! -JustinN>

Removing sand from a refugium 1/21/07
<Hi Keith.>
I bought a nice 55 gallon tank with a 20 gallon refugium from someone who had a long-standing reef tank and refugium.  
<Good deal. I love used equipment almost as much as new!>
He is located about 45 minutes away.  <Good to know... ;) > He gave me a really good deal as he was got a nice 120 gallon setup. <???>
We planned it out and I went and picked it up about 2 or 3 months ago.  He kept the tank running for me as he took about two weeks while slowly adding things to his new setup.  We kept most of the water and transported the refugium as carefully as possible to try to keep the bacteria alive to help cycle the tank.
<Should not be a problem if sand was kept moist at all.>
I had 40 gallon with about 70 pounds of live rock, a Mandarin <sic> goby, liverock, aragonite <sic> sand, a cardinal, Astrea nail <[Sighing, shaking head...] Nail?>, a 10 gallon refugium underneath the tank with some Chaetomorpha.
<Sounds good so far.>
I got the new tank back to my house and got it set up as quickly as possible, but did make a mistake with salinity for a day or two and then got the salinity correct<ed,> then waited a few days and slowly started transporting the contents of my tank to the new tank.  
<What constitutes a "mistake with salinity"? A few days may turn out to be a little short on the wait for a potential re-cycle.>
I tested the water for a few days and all seemed well.  
<Mmm... ok.>
I didn't add anything else to the tank for about a month and then added 10 Astrea snails.
I added some base rock I had in the process as well which as starting to look alive again.
<That is a good thing indeed.>
Recently, I had a red slime outbreak (Cyano) and started noticing the live rock was fading.  I did some reading on your site and read about phosphates and couldn't figure out where they were coming from.   
<Food, water change...>
After reading and chatting with a few friends, I look back and realized I was probably feeding to<o> much food<,>
<Mm-hmm.>
so I cut back feeding to every other day and did a few water changes over the next month but it was still present.  So I did the following after doing some research: Added some Caulerpa to my refugium,
<Good, will compete for nutrients with BGA.>
Added light in the refugium (was a 60 watt house light I kept on all the time) with the purchase of a 12 inch 36 watt Coralife compact fluorescent.
<Likely, will be more than enough.>
Changed his power compact light he had (it was about a year old) and got a new one
<Ok.>
Added a carbon bag to the refugium getting some good flow main tank. <Hmm?>
Purchased a pair of phosphate pads where you keep one in for 24 hours then discard, and put the second one in for 48 hours then discard along with some Cyano powder you can add to the tank which has gotten rid of the Cyano before I even discarded the first pad)
<Uh-oh, sounds like a possible E.M. or similar product aimed at killing the BGA, instead of reducing the levels of it's required elements. We used to use Erythromycin in the 90's to try to get rid of Cyano and snot algaes, but it had the undesired effect of killing of your beneficial nitrifying bacteria as well as basically dispersing the Cyano in dissolved form (bad) into the water column.>
Also siphoned some sand out of the main tank, rinsed it thoroughly making almost free of anything and placed it back in the tank.  
<Not neccessary.>
Added a powerful powerhead (Rio 2100) getting some good circulation plus another standard powerhead
<Very good step in thwarting BGA.>
Here are some questions I hope you can help me out with.
<Will try...>
1. After thinking about it, I would think that I would have a ton of die-off in my sand.  
<In the form of ammonia, not usually phosphate.>
When I got the tank, he left me an inch or two of Southdown sand in the main tank and probably about 5 inches of Southdown in the refugium that he had up for years.  Can I siphon all of this sand out of the refugium, then just add about 3 inches back in the refugium with hurting the natural cycle of the tank?  Any bacteria there I should worry about?
<I would just add to the existing substrate, as I don't see a need for removal of the older, established schtuff.>
2. I recently found some ar<a>gonite sand filling about half a bucket.  I rinsed it thoroughly and added some to main tank.  A week later, I vacuumed some more sand out, rinsed it thoroughly, and added it back to the tank.  Is this ok to do every two weeks or so, or even every week?  
<Above and beyond what is required, here. Furthermore, any rinsing of established media (LS, LR etc.) should be done in tank-water.>
I love my Mandarin <mandarin>
who has been with me for 3 years, and don't want to disrupt the sand bed, but want to get rid of any die off<.>
<You are overreacting, IMO.>
I know I must have gotten that aiding the phosphates?  
<If you allow the new system to properly cycle, and confirm the cycle with testing, you should have no probs. I would expect the cycle to be quite abbreviated.>
Let's say I took out a little sand here and there each water change then adding it back after rinsing thoroughly.
<Cut that out! ;) >
3. On my current refugium, I now have the Coralife lighting, but I did leave the 60 watt bulb shining down on the 20 gallon refugium, is this ok or two <too> much light?
<Mmmm... probably, yes. Do some searching re lighting requirements for refugiums.>
Thanks again for your help and taking part the most informative/educational aquatic website I know to date.   I stay glued to the site!
<Thanks for participating!
-Graham T.>

Fuge substrate question-DSB, MMud, both?   12/31/06
Hello to all, thanks as always for your contribution to this great site and our hobby!  My question should be a quick one this time.
  I have dedicated a 12x14" fuge in my 55 gal sump(120 gal tank).  I have read and read about sumps, DSB's, MMud and fuges but I can't find a straight answer for my setup. What is the best substrate setup and can I layer this for better function and to keep the mud down?  
<Mmm, the arrangement of baffles and subdued water flow is useful here>
  I have plenty of pink Fiji, crushed shells, 1-20lb bag of live sand and 2 gallons (16lbs) on Carib Sea's mineral Mud and plenty of small live rock rubble to add.  I have a recovering Imperator with HLLE and want to use the Mud.??
<Again, useful here>
  I was thinking about the crushed shells on the bottom 2" then the sand for 2" then the mud for 2" then more sand for 2" to keep the mud from flowing all over.  How does this sound?
<Mmm... the mud will still get about in time... do shoot for a slow flow rate of water through the refugium area... a handful of turn-overs per hour or so>
  Should I not use the shells?
<Up to you... I would>
I figured it would be good for critters.  Is there any preferred order in layering a substrate for the fuge?
<Mmm... yes... the easier-mixed material on the bottom either by itself or blended with other material (calcareous is better to reduce the chances of too-much reduction/acidic chemical behavior and its consequences), with some less-voluble material on top...>
Is layering not recommended?
<By some... Depending on what all is being layered IMO...>
Also, what is your most recommended algae to grow in the fuge?
<Likely Chaetomorpha and/or Gracilaria currently. Please read here: http://www.wetwebmedia.com/refugalgfaqs.htm
and the linked files above>
  Thanks again for your time.
  Randy
<Welcome. Bob Fenner>

Re: Fuge substrate question-DSB, MMud, both?  1/2/07
Bob,
  Thanks for your response.  I guess I should have included that the fuge is fed on one side of the 55 sump with the skimmer on the other side with both draining to the middle pump area.  So, yes I do have a separate feed for the fuge that is completely controllable.  
<Great to know, have arranged on your part>
  With this said, What would be the best order and depth for the following additions?  For both efficiency and flow control issues low flow)?  What should I, and should I not use?   
  crushed shells
  live Arag. sand
  2 gallons Carib sea Mineral Mud
  Lots of dried pink Fiji
   <Mmm, all the Mud first, then the two sandy substrates mixed together (rinsed first), then the shells on top>
  Thanks again and Happy New Year!
  Randy
<And to you as well. Bob Fenner>

Refugiums...Chaeto Without Sand?? 10/16/06
I am about to go pick some Chaetomorpha up for my first refugium ever, but I had a question first. I have been reading over the website about having sand beds in your refugium but I talked to the owner at the local fish store and he said if you use Chaeto that you don't need sand because its not a rooting macroalgae can I get away without adding a sand bed.
<You could, but you are defeating the purpose of having a refugium.  The sand/mud provides a habitat for all the beneficial critters that will consume your detritus/organic matter.  "Miracle Mud" also has the advantage of supplying calcium and iodine to the system.  In my opinion, a good product.  Read here and linked files above, for more info on refugiums.  http://www.wetwebmedia.com/refugium.htm>
Thanks.
<You're welcome, James (Salty Dog)>

Refugiums...Chaeto Without Sand?? - III - 10/20/06
I have changed my mind about adding a sand bottom to my refugium after what you told me. But I am adding Carib sea mineral mud, a one gallon container, not sand. My refugium is 12"x14" in my sump. I made my sump using the pressure locking sump baffles article. But anyways, will this be enough mud to cover what I need in this relatively small space and will a refugium this size have a positive effect on a 120 gallon system.
<One and a half to two inches of mud should be fine.  Any refugium will have a positive effect on a system.>
And the critters you were talking about how do they end up in the main display or am I just confused here.
<Generally find their way there from the live rock.  You can also jump start it by adding some copepods to the refugium.>
And what kind of critters should be in there.
<Pods, small worms, etc.>
And what is the best way of getting them.
<Fresh live rock will usually contain enough critters for a starter cultivation.  Have you read the links I've posted?>
Thank you for all your help.
<You're welcome.  James (Salty Dog)>

Refugium Substrate Questions
Hi folks,
<Scott F. with you tonight>
I am going to be upgrading my 4 yr old reef tank (55G w/hang-on filter) to a 75G w/30G sump/refugium. I plan to seed the refugium with some of the seasoned crushed coral/aragonite mix from the old tank. What substrate(s) & depths would you suggest for the tank & sump, for best biological filtration? None of the inhabitants require anything out of the ordinary.
<You can use a course substrate if you're trying to cultivate amphipods, medium for copepods, a deep, fine substrate for enhanced denitrification>
Even though I am transferring water & live rock & corals into the new system, will the tank "cycle" due to new substrate in the main tank? 
<In all likelihood, yes. Do test ammonia/nitrite for a week or two before adding new inhabitants>
I am planning on weekly 10% water changes, siphoned from the main tank gravel only, never touching the gravel in the refugium. Is this the correct approach?<if you have a fairly deep sand bed (greater than 3 inches), you really should not disturb the sand bed in the main tank. Ditto for the refugium. You don't want to disrupt the nitrifying processes occurring in the sand bed(s)>
Thanks to whichever of you is kind enough to answer, and special thanks to Bob for TCMA. Could you please write similar guides to finance, parenting, and car repair? ;-) 
Scott
<How about it, Bob!><<Easily done. Bob F.>>

Refugium Question  - 09/10/06
Greeting from California:
<And to you from lousy Michigan>
Once again I find myself turning to the WWM crew for advice, you guys are AWESOME!!!
I am adding a refugium  to supply food  for the 125gal reef tank of softy corals, fish, cucumbers and crabs/snails.  With the main tank being DSB of sugar sand and live rock, am I missing the boat by also doing a DSB/live rock in the refugium, or would I be better off with Miracle Mud or something else?? As for plants was going with Chaetomorpha as the macro algae.
<You're not missing the boat, but my choice would be Miracle Mud.  It does supply a good deal of calcium and iodine to the system.  The Chaeto will do just fine.>
Thanks again for shining the light at the end of the tunnel.
<You're welcome.  James (Salty Dog)>
Randy

Small Refugium DSB - 07/26/06
I made a 5 gallon refugium that sits behind my main tank, a ten gallon, with the goals of nutrient export, pod production, pH stability and increased water volume.
<<Excellent>>
I was planning on putting Chaetomorpha, live rock rubble, and some sand in this refugium and running it on a reverse photoperiod.
<<Okay>>
My question is would I see any benefits from a deep sand bed in this size refugium (the sand area's footprint would be 5"X15") or would I be better of with a shallow sand bed and more water volume?
<<Everything is relative my friend...considering the small size of the display, this particular DSB could indeed provide some benefit>>
Thanks a lot for any help you can give me.
Eli
<<Is my pleasure to assist.  Regards, EricR>>

Refugiums ... flow, DSB   6/1/06
Hello Sir or Ma'am
<James today>
I have a question that has not seemed to have been asked (I have looked for the past 3 days for the answer) I am setting up a 35 gallon refugium for my 200 gallon reef tank. My tank is about 3 weeks old (if that is of any interest or relevance). I am planning on attaching a Maxi-Jet 1200 or Mag 3.5 for flow. I will be pumping up the water from the sump and then draining it back into it. My question is this: I would like to run a fuge with Chaetomorpha and an 8 inch DSB. I will be running a reverse lighting schedule. I am wondering if that flow will either be too much for the Chaeto or too little to properly provide aeration for the DSB. I understand, per Bob F., that he likes only a little flow over Chaetomorpha and doesn't buy into tumbling it. I also would like some tips for maintaining a DSB other then "stirring" it lightly once a month and adding a inch or so a year.
<Matt do read here and related links above on both sites.
http://www.wetwebmedia.com/refugium.htm
http://www.wetwebmedia.com/deepsandbeds.htm
Thanks again
<You're welcome.  James (Salty Dog)>
Matt

Live Rock In The Refugium - 04/28/06
Hey everyone,
<<Hey Marc!>>
I am keen for some advice regarding the refugium I have set up for my 120 gallon tank.
<<Okey Dokey>>
I have several pieces of live rock in my tank that have green hair algae growing on them.  The algae is by no means out of control and I must admit I don't mind a little hair algae and consider it just another component of a reef system.
<<Ahh, me too!>>
My question is regarding the use of one of these pieces of rock in my refugium.  I have a wonderful piece that is directly under my main sump return that has a myriad of life including hair algae,
coralline algae, small sponges growing on it and other life such as inverts etc.  Would this piece be an ideal candidate for the refugium of would the hair algae pose any ongoing issues?
<<Nope...would be just fine>>
I would also like some advice regarding circulation.
<<Ok...use lots of it <G> >>
I have a manifold around the top of the tank with four outlets
(each corner) putting out around 500-600 gallons in total and the return from my sump an extra 500-600 gallons.  On top of this I circulate around 500 gallons through the rock work to try to minimize detritus build up in between and below the rocks.  The main concern I have is the effect on my LPS corals such as the goni's and frogspawn.  They are pushed around in all directions quite vigorously and I am worried this may have some longer term
impact on them.
<<It will...a positive impact.  As long as you are not "blasting" them directly, the random turbulent flow you describe is quite welcome and beneficial>>
Although currently they seem to open well and look healthy.
<<Indeed!>>
Have I gone with too much flow or should I maintain it considering I am adding some varied SPS corals to the tank currently.
<<You're fine mate, you could even add a bit more>>
Thanks for any help and thanks for the advice on the calcium reactor.
<<Mmm...don't know who that was, but like me, I'm sure they were happy to assist>>
P.S. - I am super keen to get to the states to get a chance to get to some of the conferences/expos you have.  We have very little opportunity in Australia for this type of gathering.
<<Is a shame...these conferences are truly a blast!>>
Cheers,
Marc
<<Take care my friend, EricR>>

Any Trouble With Rubble? (Use of Live Rock Rubble In Refugium)  - 04/16/06
Just curious to your thoughts on using the 'mud' and assorted silt/debris from the bottom of a retailer liverock tub to top off crushed coral/sand substrate in a refugium?
<As a big fan of the use of "rubble" in our systems, I'd give you unabashed support for using this stuff! As long as the rubble has already been "cured", and won't be a source of a possible ammonia spike after introduction, I'd definitely use it. It's an excellent microhabitat and possible food source or foraging area for many fishes and invertebrates. Yes, it could accumulate some detritus, but this stuff is a natural food source and the possible drawbacks of detritus in our systems may be overstated, in my humble opinion.>
I'm using Steven Pro's Aquaclear 500 DIY fuge and so far working great, but I'd like to boost my pod populations. I'm faced with purchasing cultured pods (all the liverock added to the tank was dried base rock), or wondering if using some of the above mentioned 'mud' would add in sufficient numbers.
<Well, more coarse substrates and rubble tend to harbor populations of copepods, but I'd recommend a starter culture either from a source like Ocean Pods (BTW, the owner, Adelaide Rhodes, is pretty much THE authority on copepods!) or Indo Pacific Sea Farms, or even from the refugium of a friend's aquarium.>
Are there drawbacks to using this material (flat worms, etc) and would it introduce too many organics to the system.
<Like with any living creature that you add to your aquarium, I strongly recommend quarantine (yep- even for rock!) as a first line of defense against the introduction of potentially unwanted "guests". This material, in my experience, is no more problematic to use than any other live rock, with the possible exception that you may find the diversity of life that accumulates in rubble over time fascinating, and set up an all rubble system!>
I'm in the process of getting some Chaetomorpha to add to the fuge, to give them food source/shelter, but just wondered your thoughts on the use of the material in aquaria.
<Go for it!>
A secondary question, in the display tank (20L) with crushed coral/shell mix substrate, I'm getting quite an accumulation of bubbles on both the rock and the substrate. The areas that are effected are primarily in the path of the return from the above mentioned fuge. I usually use a turkey baster several
times a day to blow them off the rocks and substrate. Since I can't really decrease the flow (total of about 850 gph from the powerfilter, fuge and skimmer), are there any shifters I could introduce that wouldn't have trouble with the coral/shell substrate?
<Usually, you'd be limited to creatures that work in the top layer of substrate material, so I'm thinking that certain starfishes, shrimp, and possibly some fishes (such as Ctenochaetus species Tangs, which rasp diatoms and detritus from substrate materials) would work. Take into account the bioload capacity of your tank before proceeding with additions, of course.>
From what I see most of the benthic macro inverts seem to be marketed toward sand substrates with little mention
of any other substrates.
<Agreed. You'll need to do some homework here on WWM and elsewhere on line.>
As always, keep up the good work and thanks for being an aquarist's best resource for all things wet.
<That's what we do! Good luck! Regards, Scott F.>

Refugium Plumbing/DSB - 04/15/06
Hi,
<<Hello>>
I have a 200 gallon reef aquarium.  It currently has a Tunze filtration system and Tunze protein skimmer that sit on a rail system along the top of the aquarium.  The 200 gallon has a 4-5" DSB with Aragamax sugar-sized sand.
<<Excellent>>
As you can imagine that is a lot of sand.
<<Mmm...yes...my 375 gallon tank has 950 lbs. of the stuff (Southdown)...with another 250 lbs. in the refugium>>
The way the tank is drilled or lack there of is making it difficult to plumb a refugium, but we will try anyway.
<<Ok>>
We have a 46 gallon tank with a wet/dry that we will turn into a refugium.
<<Ah, good>>
Can we use the sand from the main tank to fill the 46 gallon?  Will too much beneficial bacteria be killed in the move?
<<Bacteria, and other micro-/macro- life will be destroyed, yes.  Why not fill the refugium with dry sand with a "heavy seeding" from the sand in the display/other aquarist tanks?>>
Will it put undo stress on our fish?
<<Is a possible stressor to the whole system>>
I want to do whatever is going to benefit the fish.  So if that means leaving the main tank alone and buying new sand that is what
we will do.
<<Unless you're planning to remove the fish and "restart" this tank I would use new sand and seed it as mentioned.>>
We were thinking 8 - 10" sand bed in the 'fuge.
<<Sounds good to me...am a big fan of deep sand beds>>
We want whatever is going to help us with our nitrate issues.
<<I see>>
We usually have 20ppm and I want that down to 0.
<<Indeed, much to high for a reef system...but zero-nitrates is not necessarily good either.  For the benefit of your corals, a nitrate reading of about 3ppm can provide some much appreciated nutrient benefit>>
I figure the added filtration will help.
<<As in DSB?...yes>>
Our system is going to be very difficult to plumb the refugium. There is no place for an overflow box.
<<Can you lower the water a bit...drill a throughput high on the backside?>>
The access ports are the only openings and have a 6" gap to the side of the tank.
<<An acrylic tank then?  Will be quite easy to add some bulkheads>>
Plus we have a hood that covers the entire tank.  I posted to the WetWebMedia Chat Forum in hopes to get some suggestions.  Nothing
so far.  I even posted a diagram of what our tank looks like from the top.  Any ideas from you would be great.
<<Spend some time reading here (http://www.wetwebmedia.com/pbholesfaqs.htm) and researching among the linked threads.  I think your best option is to drop the water level in the tank a few inches and drill a/some holes through the back/side of the tank for bulkhead fittings.  My tank is a "in-wall" unit viewable from front and back...I drilled holes for 6 bulkheads through the end panels 1 3/4" inches from the top, which feed both my sump and refugium...it is do=able>>
Thank you, Jeri
<<Quite welcome.  Regards, EricR>>

Refugium Confusion? Question about Mineral Mud in a refugium  - 04/04/2006
Hello,
<Hi there! Scott F. with you today!>
I bought a CPR Small Refugium.  I am going to hang it off the side of my sump.  I have a 56 gallon main tank.  I really liked the section in the book 'Reef Invertebrates' about refugiums.  The main purpose of the refugiums is to harvest food for a Mandarin Goby that I am planning to get.  I would also like to place some Macro Algae in the refugium as well.  I bought some Mineral Mud and was wondering if it is ok to make the bed like 3 inches deep and then top it off with some sand?
<I see nothing wrong with that, myself.>
Do I need to top it off with the sand?  What are the benefits to that?
<You don't have to top it off with sand, but it will help keep the mud from getting back into the display tank due to flow.>
What is the ideal depth for the mineral mud in the refugium?
Thanks,
Jason
<I'd shoot for two inches or so, myself. This will be a sufficient depth for many macroalgae to establish themselves. Good luck with your 'fuge! Regards, Scott F.>

Refugiums/Substrate/Husband Driving Wife Nuts  - 04/02/06
Hi Crew,  <Hi Kris>
Your advice please.  My husband is driving me crazy (not that you can help that), but he's planning out his reef and refugium and has me surfing nonstop for info.  OK, the latest crisis is what to put in the bottom of the refugium.  He had settled on a DSB and now someone put the bug in his ear about Miracle Mud and that it's the only thing that will work in a refugium.  So to mud or not?  I can't find a definite answer in your archives.  Is this stuff really that great?  <I'm presently doing an evaluation on a system that is using Miracle Mud.  This was started 2/1/06 and to date, it appears beneficial.  My calcium levels remain normal without adding any supplements although I do test on a regular basis for same.  The mud is supposedly high in trace elements including iodine.  I have noticed since using the mud that the yellow polyp colony has increased its population more so than without the mud.>
Mud brings me to my other question.  We live in south Florida and there are mangroves in abundance.  Could I go dig up some mangrove mud and bring it home for the refugium or am I asking for bigger problems?  <I wouldn't, believe that mud is going to be very high in nutrients.  James (Salty Dog)>
Kris

Refugium/Substrate  - 04/02/06
James,
Thanks for the quick reply.  So if we go w/ the MM what's the deal with only a 1 inch depth of substrate in the display tank?  We've already put in a 3 inch bed of Carib Sea Aragamax select (not live sand).  Is this not going to work now?  <The Miracle Mud is for the refugium only, not the entire tank.  James (Salty Dog)>
P.S.  I didn't think using natural mud from the mangroves would work, but thought it was worth asking on the slim chance it would.
Kris

Travertine As Bio Material? - 02/25/06
Hello.
<<Howdy>>
I got some great advice today.  Thanks to everyone.
<<Welcome>>
Just one question that is not anywhere on the site. (Now it will be.)
<<Ok>>
My LFS sold me about 30lbs Travertine <<?>> for biological filtration in my sump.
<<curious>>
I can't find a single person with Google who uses this.
<<Likely not>>
This worries me.  Thoughts?
<<Firstly, I don't think you need worry...no harm should come to your system from this material...though that doesn't mean the possibility of introducing a contaminate is ruled out.  My knowledge of Travertine is as a material used for decorative stonework in up-scale homes/buildings.  Though it is a calcium carbonate/CaCO3 based material, it is fine grained/dense (polishes up nicely) and less than a good choice as a bio-media in my opinion.  It likely won't hurt your tank, but I doubt it will help much either.  You would be better off replacing this with ordinary live rock rubble for biological filtration.>>
Thanks in advance,
Christopher
<<Regards, EricR>>

Refugium Substrate/Dosing Kalkwasser - 02/18/06
Hi Crew,
<<Howdy>>
Still reading and learning on a daily basis here - kudos to you all on the provision of such a fantastic resource.
<<Thank you, a collective effort.>>
55 Gallon (200 litre) main tank (cube), Miracle Mud ecosystem sump, 150w MH - almost ready for salt water - yippee!!
<<Yea!!!>>
Main Tank substrate (aragonite) to be ½" or less deep (aesthetic rather than functional here & more natural than bare bottom for livestock I think).
<<Me thinks so as well.>>
I'm confused on grain size but thinking of CaribSea Fiji Pink (0.5-1.5mm grain size) ideally non live (cheaper & I'll have LR anyway so life/bacteria should colonize) but might be "live" (bacterial only) depending on what I can find in the UK, would this be a suitable choice regarding composition and particle size?  Or should I go finer?
<<The Fiji Pink will be fine.>>
Would this substrate need a rinse at all or just straight in after LR (positioned directly on tank base)?
<<For a new setup rinsing is not necessary.>>
It seems from my reading that it will settle & the fine aragonite "dust" will be beneficial anyway.
<<Agreed>>
In this thin sand bed I plan narcissus snails <<Nassarius>> or similar, how many should I aim for (55 gal tank 24" cube ½" deep bed)?
<<I'd start with a dozen or so.>>
Connected to this is my choice of substrate for a 2nd refugium (to be added at a later date).  Am I right in thinking that the MM/Chaeto fuge would be quite good for copepod, phytoplankton and zooplankton production?
<<Yes>>
In which case would I be better selecting a larger particle size for the 2nd fuge substrate to encourage bio diversity - amphipods etc. or would something similar to the Fiji Pink be more appropriate (probably going to be 4-5" deep here) & concentrate on copepods etc?
<<I think the Fiji Pink would serve well here also.>>
Main sump is Miracle Mud with Chaetomorpha, I understand that some people light 24/7 (mainly Caulerpa growers to hold in stasis) however Anthony Calfo (fantastic coral prop book by the way! - great resource for us learning reef keepers/moist gardeners) recommends a more natural photoperiod & I agree - would a 10-12 hour lighting duration be appropriate here?  (mud bed is 11 ½" x 10" lit by 20w PC spot lamp @ 6500k)
<<Indeed...on a cycle opposite that of the display tank to assist with pH elevation.>>
I plan to install lots of LR - would 1 - 1.5 lb per gal be about right bearing in mind the miracle mud/Chaeto filtration?
<<I think you could/should get by with less, especially considering your addition of the refugiums.  Less rock will actually look better and give your fish room to swim.>>
Views seem to differ regarding the lighting of LR whilst it is curing, my LR will be shop cured (however I understand some further curing/die off is likely).
<<Yes...unless the rock has been at the shop for some weeks/months you will likely experience a cycle.>>
In this instance collective wisdom seems to indicate that LR should be cured lit, is this likely the best approach?
<<Subjective...but I ran my lights over mine while curing.>>
When the tank is up & running I'm probably going to run the MH lamp for 8 - 10 hours per day and 7-8" above the water line if you think this is appropriate, would this lighting duration be suitable for finishing off the cure of the LR?
<<Would be fine...I'd increase the light period to 10-12 hours once you begin stocking.>>
I use RO/DI water for my water changes and top off, water change water is heated & aerated for 24hrs before being buffered, another 24hrs before being salted & generally sits about for another day or two before use so should always be nicely aged.
<<Excellent!>>
I tend to split some of this off for top off after its been buffered (before salted obviously!).  For the new tank I plan to install an auto top-off with a reservoir (20-30 litres) would this reservoir need to be aerated/stirred continuously or would it be ok just sitting?
<<Should be fine without aeration.>>
(1.5 litres or thereabouts top off per day) I'm assuming it won't need heating.
<<If added in small increments throughout the day it will be fine.>>
I am also considering a weak Kalkwasser solution for top-off or would this be better dripped at night?
<<I prefer to add Kalkwasser through the use of a Kalk-reactor in conjunction with my auto top-off, but using a nightly drip is quite acceptable as well...I say use whichever is most convenient for you.>>
I'll be in touch for you to cast your eyes over my stocking list soon if that's OK.
<<I look forward to it.>>
Many thanks,
Chris
<<Cheers Chris... EricR>>

Refugium Methodology...Reverse Flow DSB? - 02/11/06
Hi,
<<Hello>>
I have a 210g reef tank (200lbs. LR and a large number of corals) with a 40g sump and a 40g refugium.
<<cool>>
Lighting is an Aquamedic space light with 3-250W 20K HQI.  My skimmer is an Aquamedic model, not sure of the model number but I have found it to be excellent.
<<ok>>
The pump for the return is a Dolphin 3000gph.  I have been toying around with various ideas to try to improve on the refugium because it's not doing what it is supposed to do which is act primarily as a nitrate reducer.
<<I see...>>
In talking to various people, I came across an idea that intrigued me but have not been able to verify it.  In a nutshell, it uses a plenum (~2"tall) and has approximately 5-6" of sand on top.
<<You don't need the plenum...>>
The interesting part is that a pipe is run under the plenum and water is slowly pushed thru the sand and then returns to the main tank.
<<Hmm...ok>>
I have not been able to verify the effectiveness of this, and while I don't mind experimenting, I would prefer not to do anything that would have a truly detrimental affect.  Any ideas would be great.
<<I'm not familiar with this methodology...for my two cents, I would employ a simple lighted vegetable refugium with a 6" sugar-fine DSB and Chaetomorpha algae.  But if you're interested, do set up a test system as described, and let us know your findings.>>
L
<<Regards, E >>

Refugium Methodology...Reverse Flow DSB? II - 02/13/06
Wow!  Thanks for the fast reply.
<<Welcome>>
I'll try the DSB with sugar fine sand and algae.  I'll find a tank and set up the test and let you know.  Again, thanks for such a fast reply.
L
<<I look forward to hearing about the results.  EricR>>

Half sand/half mud refugium   2/10/06
Hi guys.
<David>
Dave here from Colorado. I have designed and built my own hob refugium for my 50 gal. marine tank. First of all the specs: The refugium is 36" long, 5" deep, and 12" high. I have designed a support system to keep the  weight off the back of the tank.
<Good, considerable>
I wanted to go with as much volume as possible, and still have it attached to the back of the aquarium.  I will still have enough room on the back of the main tank for mechanical filtration, and plan to move my skimmer to the side of the tank, my two power heads for cross current will also fit in this set up. I designed the baffles in such a way that will (hopefully!) keep the turbulence to a minimum, since I wanted to primarily use Miracle Mud as the substrate. I am going to use a Maxijet 900 (230gph) for the water flow.  I put a 4 1/2" tall divider in the middle of the refugium, in case I wanted to experiment and use a 2" bed of Miracle Mud in one half of the refugium, and a 4" sugar grain sized aragonite live sand bed in the other half. I also am going to put in 7-10 lbs. of good live rubble rock as well. My main tank has 60 lbs. live rock & 60 lbs. of live sand. I have 6 fish in my 50 gallon tank (a pair of true Perculas, a Royal Gramma, a Six Line Wrasse, a Cherub/Pygmy Angel and a Humbug Damsel that my wife won't let me trade-in). All are healthy and doing well-no discernable problems. I also have a rose bubble Anenome (I think I know what you're going to say about that!) that the Perculas go crazy over-the Anenome is doing well in a 1 1/2" PVC pipe wedged in the rock. I have the usual assortment of snails & sand sifters, 5 hermit crabs and 2 shrimp (one peppermint and 1 cleaner shrimp). I also  have some star polyps that appear to be thriving. My water parameters are good,  ) 0 ammonia & nitrite, .1 PPM Nitrate, pH 8.3, specific gravity at 1.023. I want to eventually keep a few soft corals (not a lot) along with what I've got (although I do want to replace the Damsel with something else!).
<Best leave it...>
Now for my 3 questions (drum roll!)-
1. I am now leaning toward going the half mud/half sand substrate route in the refugium, instead of all mud-do you see any potential problems with that, or am I better off going with just one type of substrate for the refugium?
<I would experiment as you state, with both>
2. I'm thinking of trying Gracilaria in one half of the refugium and Chaetomorpha in the other half-the way I've designed it they (hopefully!) shouldn't intermingle a lot, but will they emit toxins to try to eliminate each other?  If so, which one would you go with?
<Both here as well>
3. If I can ever talk my wife into trading in the Damsel, is there any small/miniature/dwarf Tang that you know of that could feasibly do well in a set up like this?!!!
<Mmm, not really... for the long-haul... next, larger tank...>
Thank you-your site has been very helpful, I scour it all the time!
Dave
<Me too my friend, me too. Bob Fenner>

Refugium setup    1/25/06
Hi WWM Crew,
My question deals with setting up a refugium.  Although these questions may be basic, I have not seen them asked
I have a 27 gallon, 20 inch high acrylic aquarium on the way that I plan to setup alongside my 75 gallon 8 month old reef tank.  After reading your
FAQs, I am settling on a six inch DSB of sugar fine aragonite.  My question is regarding the setup.  I figure that adding new sand and water to the refugium and then immediately hooking it up to the main tank could cause stress/death on the inhabitants in my tank.
<Mmm, not so...>
I picture cloudy/out-of-balance water pouring into my reef tank.
<Pre-rinse and allow the fine substrate to settle... add a bit of the "old water" to this tank... leave be for a week or two...>
Since the fuge is so large, should I set it up independently, possibly with some water/sand/rock from the main display, and let it cycle for a month or so?
<Oh! Yes>
If so, how can I then slowly and effectively bring the two tanks to equilibrium (i.e. the water parameters)?  Again, I ask this because the fuge is so large (about 35% of the main tank volume).
<"Boris Karloff" (mix the water back and forth with a pitcher.) With or sans blood-curdling laughter>
Also, to jumpstart pod growth, I was planning on adding "Ocean Pods".  How long should I let the fuge settle/cycle before adding these?  
<The month or so>
Since my gravel will be fairly fine, will Gracilaria algae and a few Shaving Brush plants be sufficient for pod growth....or will I need Chaetomorpha?
<Mmm, in this sized refugium I might try two or all three>
Finally, my goal is to successfully keep a mandarin.  Do you find that pod reproduction/growth would decline over time; would I need to supply my fuge with something like "ocean pods" on a monthly/etc. basis?
Thanks again,
Tim
<Only time/experience can/will tell... but I give you good odds that "this will do it" if there is not too much food competition in your main system. Bob Fenner>

Vague questions/answers re lighting, refugium substrates  1/16/06
Hello,
I was wondering what is the best combination of bulbs for my 440 watt VHO setup. I know it is a bit inadequate but I would like to keep an SPS toward the top. It is 4 bulbs and I can choose URI's day sun, actinic white and actinic blue. Whatever combo will provide the most useable light for the corals.
<Likely the whites in the 10-15k range>
Also, I was just making sure... as for the sandbed in my fuge, all I need to do is have a sandbed with no plenum or anything like that right?
<Please see WWM re... there are many design options, alternatives. Most folks avoid plenums as unnecessary, but some leave out substrates as well. Bob Fenner>
Thanks for any help, Dan

Refugium Questions 10/13/05
Hi once again, I have been looking up on a refugium, I was looking into the AquaFuge External Hang On Refugium, and I have a few questions. In my main tank there is 2 actinic blue and 2 actinic white fluorescents producing a total of about 6 watts per gallon on my 75 tank, since the refugium is hanging onto the back of the aquarium will it still need it's own lights, or will the lights on the main tank be enough (I know about the lighting the refugium at night thing but...$$$) 
<The light coming from your tank will be marginal for the refugium. Also, there is a lot of benefit from lighting the 'fuge while the tank lights are off. If you shop Wal-Mart or Home Depot type stores, you can find many choices of fairly inexpensive small compact fluorescent fixtures that will work well for a refugium.>
Also my tank has a wet dry 125 gallon capacity and a sea world systems protein skimmer, My tank has been up and running for 3 weeks, is it too late for a refugium? ( I always thought it was never too late for a refugium!!) Also once I got the refugium set up, would it be wise to remove the bio balls from my wet dry. 
<It is never too late for a refugium! As long as you have at least 1lb per gallon of live rock, you can certainly remove the bio-balls from your wet/dry (independent of adding the 'fuge).>
The hang on refugium states that it is 19 1/2 by 4 and 1/2 by 12 high (inches) how am I going to fit LR into that refugium, and if so, how much would you recommend. My intended use for the refugium is for all of its nutrients, pH, Nitrate, Nitrite, and Ammonia, the pods' would be fine too even though I don't plan on having a mandarin. I was looking into some assorted Caulerpa packs, but have since heard some conflicting stories about this macro, any suggestions on other types of good ol' macroalgae?
<Many dealers will sell "Live Rock Rubble", and often at a discount. These small pieces will fit easily into that space. Do keep in mind that rock is not mandatory in the 'fuge. As for macro choices, Caulerpa is not so much of a problem in FO tanks as it is in reefs where it's noxious chemical defenses can stunt coral growth. It can still become invasive in the display though. Chaetomorpha is an all around better choice, if not quite as fast growing. Macros are available for free or for trade at most local marine aquarium society meetings.>
Last question, I swear, since the refugium is a hang on the back, how could it be connected in any way to the main display, I don't exactly want a bunch of hoses in my main tank, do you know how these work? (sorry, I thought of another question) And other than the maintenance of cutting the macroalgae you put in there, are there any other maintenance issues involved with a refugium? 
<Connections will vary with the exact model, but ideally water should be pumped into the refugium and passively drain back into the tank to spare microcrustaceans a trip through the pump. That said, you may want to consider placing the fuge in/on your wet/dry where it and it's plumbing will be out of sight. Although this means a trip through a pump for the critters, this is a minor compromise. Unless you find that sediment and detritus is accumulating in the refugium, very little maintenance is required.>
P.S. I plan on having a 6 or 7 " sand bed of Marine BioSediment, good brand? Thanks a million, Clare 
<I don't know anything about this brand, but any fine grained (sugar fine) calcium based substrate will work well. Best Regards. AdamC.> 

Refugium Sand Bed - 09/04/05
Hi guys, keep on the good work.
<<Hello>>
I'm upgrading to 60 gallon tank with a refugium. What kind of sand bed that I should have in the refugium?
<<Six inches of sugar-fine aragonite sand.>>
Can I use some sea sand for more natural filtration?
<<I wouldn't...too much risk of introducing pollutants/pathogens.>>
Also I plan to enrich the refugium by adding some plants, small crabs or perhaps shrimp?
<<A "single" specie of macro algae is fine...the crabs/shrimp defeat the purpose of the refugium.>>
The size of the refugium is 30 gallon.  Thank you in advance for your advice.   
<<Please have a look here and among the associated indices: http://www.wetwebmedia.com/refugium1.htm
Regards, EricR>>

DSB in small Refugium, what to do in main tank, and getting the tank going? 8/29/05
Hi WWM Crew,
<Marc>
The obligatory opening kudos to you all, because you truly are my lifeline in beginning in my adventure into a reef system.  I have questions in 3 areas, but let me start with setup first:
-72gal bowfront (48Lx20Hx12/18 deep)
-55gal sump - 3 sections: skimmer and heaters -- baffles 17" high -- return -- baffles 16" high --  refugium) where the downspout is split into the 2 end sections so the flow through the refugium is slower.  Plan to use refugium on RDP with Macro algae (going to use Chaetomorpha)
-ASM G2 w/Sedra 3500 for skimmer
-Mag 12 return (which is plenty because AGA tells me the Durso provided w/ my reef ready does about 600 GPH), return split into 2 rear corners with water coming in 4 inches above bottom of tank)
<... this/these returns have check valves? I really don't like these arrangements... many, too many instances of "water on the floor". I strongly encourage you to re-route these discharges to above the water>
-Mag 9.5 connected to a SeaSwirl on a closed loop system (thanks to Bob for helping me through taking the return on the "not-so-