- Refugiums and Deep Sand Beds -
A very good evening to you crew... Evolving to a reef tank from a FO? <Good morning to you.>
A rundown on my set-up first.
(Should I include a rundown each time I e-mail you?) <All depends on what we are talking about... it happens often enough that folks email doesn't make it back to the original respondent. Including the relevant parts always helps.>
180g tank 20g sump (tank double drilled with two 1 1/2" holes at each end with pipes to surface to skim from top) Both leading to trickle filters with bioballs. One goes to a skimmer first, a Turboflotor 1000 and then to bioballs)
One goes straight into bioballs, (both have prefilters). Also have a Berlin skimmer in sump driven by  Eheim 1060 which doesn't seem to produce much skimmate at all.
Nonetheless, I think having two skimmers is a great idea!
Two canister filters (which I hate) one has nitrate reducing granules (haha) one has chemical, (carbon & RowaPhos) filtration. The chemical one goes through UV (55 watt) back to tank.
SG = 1.022  Ph 8.2 Temp = 80F
Ammonia = 0 Nitrite = 0 Nitrate = 40ppm - lose the Bioballs....OK, Thanks, will do. <What you need to do is address those nitrates. Your attempts to move towards a reef tank will be frustrated by a nitrate level this high. If "address" means remove the bioballs, then so be it.>
Alk = 4.23, DKH 11.8, Calcium 270! Now a week later it is 290.
I am  raising my calcium by the use of Kalkwasser... SLOWLY !!!
I would like to fire two million questions at you guys but I know I can't in one go, so here are just a couple?
First of all. Can I, or rather should I (once my refugium is set up (DSB LR Macro etc)) use an external skimmer, for the supply to the refugium? <Your choice would work, but I'd think getting unskimmed water in the refugium would be of more use> If yes (and I know you hate to be brand specific but an external skimmer that is rated for around 500G will do fine as my system will be around 250G (I live in the UK).....Any preferences? <Have no idea what is available to you in the UK... there are many good skimmers... would bet there are one or two that are make in the UK. Really do recommend trying to get around to some stores and see how these things are built... quality equipment will have the look and feel something well designed and built. Cheap equipment will feel light and flimsy.> This will simply run through the refugium and under gravity back to the under tank sump.
Also I intend eventually (after doing my homework) to keep an Anemone. Maybe a Bubbletip or one of the easiest to keep that may be a home to a clown or two. I have at the moment in my 6x2x2 display, 2x150wattMH and 2x40watt Actinics.
Would it be more beneficial to the anemones to install a 3x150watt MH at 14k each and if I do this, would I need to add actinics too? <Actually, I'd shoot for two 250's and include actinics.>
One more then I'm done... promise!
The DSB... should it be just fine grade sand? or can I just take out of my tank the mixture of fine (aragonite) and rough stuff  (crushed coral) to seed it? <Don't see why not.> Anyway I am getting conflicting ideas on how best to make this DSB as I guess the LFS's are trying to sell me Miracle mud etc. Any opinions? <This this can be pretty free form and many things will work. Don't think the coarse gravel will have any ill effect.>
Very much appreciate the information and support given freely and impartially on this great site....
Cheers, and many, many thanks crew!
Simon
<Cheers, J -- >

Refugium
I have a 180gal reef tank and would like to build a cryptic refugium with a DSB for NNR and a zooplankton reactor in the pump room behind it.  Can these be done together, or should they be handled separately.
What would the ultimate setup be for these two functions?<The refugium will act as a zooplankton reactor already it will be a safe heaven for the zooplankton to multiply.  If your refugium is large enough you should not need a separate reactor.  Cody>
thanks
Rich

-Refugium stocked with coral?-
Hello Faq Crew, Hope you are doing well today, <That I am.>
Have a few questions concerning a refugium,
I have a 20 Gallon aquarium and in the process of setting up a 135 Gallon marine tank for fish only to start. <k>
I would like to use the 20 for a refugium, will this suffice? <That would be just fine.>
If so what is the best selection of corals etc. to start off with? <Well, do you want to turn the 20 into a reef or a refugium? I would suggest doing a search through our FAQ's for setting up refugiums.>
can there be fish or should I stick to crustaceans? <Please read up on all the excellent articles at your disposal on this website, along with the plethora of emails asking very similar questions.>
being a shallow tank what sort of lighting should i look at using?
<For a 'fuge I'd suggest at least some PowerCompact lighting, 1 or 2 65w lamps should suffice.>
I am sure there are lots of different ways to go about building one but I am hoping for some good guidelines to follow so i can do it properly the first time as I would hate to make a mistake and kill off the tank and possibly cause Harm to my main display tank. <No worries, it's not nearly that complicated. Read up! -Kevin>
Thanks again
Drew Forbister

Refugium pondering 3/10/04
Hello, I have a slew of questions. First of all, I replaced my wet dry with a refugium which I am currently growing 3 types of macro with live rock.
<great to hear of the refugium... but do consider reducing to only one species of macro... it will be better/more effective for all/many reasons. Chaetomorpha or Gracilaria get my vote strong>
I have a compartment in the refugium which houses my ev-120 on my 90 gal reef ( sort of ) tank. The refugium holds about 20-25 gal. My ph seems to be a little low and I run alternating lighting on the tank/refugium. I would say my ph is about 7.8 to eight.
<very low IMO. Target 8.3-8.6  Some corals like Xeniids are clearly stressed below 8.0>
I have a digital meter coming to be more accurate. Now, one of my questions is a calcium reactor and co2 system more beneficial overall to a reef system than a refugium??
<apples and oranges... can't compare. They do vastly different things>
I was thinking of removing my fauna in the refugium to make more room for hardware,
<Yikes! keep it natural my friend... better for the tank>
Hardware would be more beneficial in maintaining calcium, ph levels etc.
<you should not need hardware for this, although a calcium reactor is a fine instrument if tuned well>
Not to mention my ev-120 is real tight in its little compartment and I could easily put both a calk reactor and skimmer in the larger side of the sump. So basically can I regulate chemically the ph and hardness and keep the refugium or would I be better off with the reactors because I want to get a little more into coral keeping??  
<you will be losing refugium benefits for the hardware here which easily can be skirted with regular Kalk dosing, water exchanges, aerating and buffering FW used for evap and salting (this is a common mistake to use raw, unaerated RO or DI water... a burden on buffers if not aerated), etc. Do reconsider the significant benefits of refugia here my friend and the ease with which you can attain stable water chemistry without mission control models ;) Anthony>

Macroalgae in the aquarium 3/11/04
Thanks as always for the prompt reply. Following your advise I will leave only one species of macroalgae in my
sump. Is it better to leave the Halimeda sp. or the Dictyota?
<neither are ideal for nutrient export or plankton production (Chaetomorpha or Gracilaria would be better). To pick between the two, however, easily choose Halimeda. Dictyota is noxious and can become a nuisance>
Do you advise to do this also in the display tank (the algae here is far from each other).
<its better, yes>
The C. racemosa is not much in the display tank and is the only algae that my Yellow Tang eats. Is it ok to leave it be in the display tank?
<its actually toxic over time (1-3 years) in some fishes allowed to repeatedly graze it. It is also competitive with corals. I do not recommend Caulerpa for any reef aquariums. Best for biotope displays instead>
Thanks, Thanassis
<kindly, Anthony>

- Hang-on Refugium Modifications -
I just bought a CPR hang on refugium for my 55 gal salt H2O tank. I was wondering, instead of there powerhead bringing in the water what about hooking my inlet to my Fluval304 canister filters outlet? In my canister I have 3 buckets 1 with carbon , the other 2 bio-material. Does this sound feasible? <It is feasible, but not something that I would pursue. The water coming out of the canister would be sufficiently filtered that it wouldn't be of much productive use to a refugium. Much better for the refugium to get raw water from the tank... I'd leave the powerhead on. Cheers, J -- >

Lighting Cycle for Algae and Heat Issues?
>Hello,
>>Hello.
>I started my refugium with Caulerpa around 2 months ago and during that time I had my two 65-watt power compacts on 24/7.
>>No need to light 24/7, my friend.
>About 3 weeks ago I removed the Caulerpa and replaced it with a good sized piece of Chaeto using the same amount of lighting.
>>Amount AND duration?  Again, no need.
>During this time the Chaeto is growing like crazy which is a good thing and my nitrates have been a constant 0.
>>Low nitrate readings are indeed a good thing.
>The bad thing is my water temperature is varying a couple of degrees throughout the day due to the heating from the power compacts.
>>Not really, a couple of degrees is certainly tolerable.  I will ask you one thing, and it's the most important thing: do any inhabitants in the display show ANY negative reaction(s) to the slight change in temperature?  Many folks get so caught up in monitoring parameters that they forget to simply use their own powers of observation, which are often much better than they realize.  
>My question is do I still need to have the lights on 24/7 for the Chaeto?
>>Not for either.
>If not what would be a good cycle to use? I have heard that a good scenario is to have the refugium lights on opposite of the main tanks.
>>Only if you're having big pH shift issues is that necessary.  With my own first system I devoted a full 1/3 of it to Caulerpa, which meant that it was lit when the corals were lit.  I had NO problems whatsoever.
>If this is the case should I gradually switch to that timeframe or will an immediate effect
not cause a problem.
>>I don't think you'll cause the algae any great stress should you decide to go this alternating cycle, it's not got a nervous system with which to react to such changes.  Plus, if you think about it, many of the animals we buy come quite literally from the other side of the world.  The time zone is quite different, and after a period of adjustment, they can fare quite well.  This would be even more true of algae.
>My concerns are if I turn the lighting time down I will get nuisance algae growth in the refugium.
>>With no excess nutrients you shouldn't.  Nitrate would not be the only issue, of course, but this is part and parcel of WHY you are growing the macros, isn't it?  ;)
>Thanks, Tom
>>You're welcome.  Marina

DIY tanks
Hi Bob!
<Hi Joe>
I am in the planning stages of setting up a reef system.  I have read most of your Conscientious Marine Aquarist and have been engrossed in the FAQs on Wet Web Media.  Both of which have been of great help to me in planning a system for my small world.
<Glad they're of service>
First question:  I am a diy guy and would like to build a tank myself.  Can the acrylic used for a salt water tank be Plexiglas or must it be Lexan?
<Either one... more a brand name than a different formulation>
I plan on incorporating an above tank refugium with a 75 gal. reef tank.  In it I plan on having a 3 in. sand bed, a piece or two of live rock or plant rock, a mangrove or two and some sea grass.  
<Mmm, do (re)consider the mangrove... really needs more sand depth>
The Refugium will be 24 in. X 18 in. and Have about seven inches of water over the sand bed and overflow into the main tank.  This would give me about 10 gal. of water in the Refugium.
<If space permits, do make the refugium sump MUCH larger... can't be too big>
Is this big enough to use as a biological filter for my main, and besides cucumbers and hermits what else should I put in the second tank to either act as filtration, maintenance and food source for a reef and some fish?
<Honestly... you'd be better off switching the tanks for function... with the 75 as the refugium... I say shoot for at least about half the volume of the main/display tank for your refugium>
I plan on Having protein Skimmer to help carry the load.  Probably a Red Sea Berlin turbo or classic.
Thank you for this great site.
Joe
<Thank you for being part of it along with me. Bob Fenner>

Re: diy
HI again!
How much sand would the mangroves require?  Are they a good source of filtration or would I be better off with a variety of other plants?
What in your opinion is best suited for a refugium that functions as a filter and food source?
<All this and more is archived on our site, WetWebMedia.com, pls peruse the articles and FAQs there>
thank you for sharing you insight!
Joe
<Glad to share. Bob Fenner>

Refugium turnover
I have a 90 gallon that is cycling to be a reef tank....i am going to
have a 20 gallon refugium mounted above the tank for macro algae and
different types of pods...(i want a mandarin goby).....from what i have
read and researched, i have found the some people say you should only have 1-2x turnover per hour?
What do you recommend?  Is that accurate.  
<That seems a little slow, however, it really depends on the inhabitants in the refugium. If you're planning on growing various species of macro algae, a turnover rate of up to 5x per hour may be sufficient.>
I have a 40 gallon sump and I was going to half of it a refugium, but the water flow would be too much wouldn't it?
<Considering I don't know what pump(s) you're planning on using, I have no clue. If you want further information, please do not hesitate to email us back with further information (mainly with the what pump you're using, how many gallons per hour it is, etc.) Hope this helps, Graham Stephan.>

- Refugium Setup and Livestock Levels -
If my boss saw how much time I've spent reading all the FAQ's I can lay my eyes on, I'm sure he'd toss my rear end!  On the other hand, just think how informed I've become, albeit at the expense of a good job. <Hard to convince me of the value of the trade off...> Oh well, priorities.  My questions:  65 gal tank, recently built and installed 20 gal refugium/sump (net about 15 gal) with almost 4" DSB thanks to you guys on this forum.  I read recently that you advise to have skimmer, refuge, then return section in that flow order, but mine is reversed.  I can't change it for several reasons--will this work o.k.? <Yes.> Also have some Caulerpa in the DSB section--will I have problems with this? <Not necessarily - you can light the Caulerpa 24/7 and that will help stop if from going sexual. Also care when harvesting to pull entire plants, and not parts of plants - all will help.> And lastly, I have med. Sailfin Tang, 1 green Chromis, 1 yellow tailed damsel, 1 small Ocellaris clown, 1 sm. scooter.  I want to add 2 more Chromis and another clown, perhaps a med. yellow tang.  Will that work, or am I pushing the envelope?? <You were good right up to the second tang - think you can add all you listed with the exception of the tang - your tank just isn't big enough for two.> Thanks, and I love your very informed site--a pleasure to read straight-forward answers, unambiguous and dead-on.  Thanks!........Barry
<Cheers, J -- >

Hitchhiker ID/Refugium/Snail reproduction - 2/26/04
Hey Crew!
Thank you all for such a great site.  I wouldn't have made it this far without all of you. <We wouldn't have made it this far without your questions. So, thank you>
I have attached an image file (not the best picture in the world) of a hitchhiker that has shown up in my tank.  If anyone has an idea of what this is I'd greatly appreciate the knowledge. <Definitely an anemone from the family Actinodendronidae See here: http://www.wetwebmedia.com/anempt2.htm>
My second question, is it okay to keep hermit crabs (blue legged variety) in a refugium? <I don't like the idea of putting hermits in a refugium as they are so omnivorous that they might eat anything and everything> My crabs, although great at keeping the sand on the bottom of the tank clean, are becoming pests to my soft corals and I would like to move them into my above tank refugium. <Really? I haven't heard of Blue Legged hermits bugging soft corals>  The refugium is about 10 gallons and has a 4 inch sand bed and contains Chaetomorpha, grape and feather Caulerpa, and probably some other plant life. I got the grab bag of stuff from the LFS. <Sounds good. Do you keep lit 24 hours a day?>
Thirdly, is snail reproduction normal in a healthy tank? <Yes. Pass them around to friends and reef club members.>
Thank you kindly,
Tony Hambley

Refugium information - 2/23/04
Hey Guys,
Getting back into the hobby and was wondering if you could share some advice on my set up and what to stock refugiums with. <well, a lot has been written about them here: http://www.wetwebmedia.com/refugium.htm please read through the faq links in blue at the top of the page as well.> My set up is a 55gl. tank on first floor of house with 600gl. per hour 1'' over flow box. below in cabinet is a 20gl. sump with in sump skimmer. From there water will be pumped to second floor of house 10' straight up with 3/4'' line by a Iwaki 55 pressure pump to a 30gl. Rubbermaid container (refugium) via spray bar above water line. 30gl. container will be gravity feed to another 30gl. container 18'' below by a 1'' bulkhead fitting 2'' below rim with 1'' line and spray bar above water line. The second container will gravity feed main tank on first floor  with 1'' bulkhead fitting 2'' below rim and 1'' line, water will be returned to tank by 1'' sea swirl. First floor tank will have sand bed and 60lbs. of live rock. <Sounds too complicated>
Any advice would be great on refugium stocking and lighting Hoping to use refugiums for filtration and food source. <Enjoy the links ~Paul>
  Thanks,
        Ron.

Small Refugium With Big Potential!
This website is awesome!  It has inspired me to take down my wet/dry with bio-balls, and build a 20 gal refugium, which I installed last night under my new 65 gal reef-to-be.
<Excellent! Glad to hear that we've been a positive factor in your system's development! Scott F. here today>
  Questions:  Because my Berlin skimmer has a footprint that takes up half the 16" length, will roughly 6-8 gallons for the refugium section be adequate, knowing that I should have more, but can't??
<Well, any size refugium is better than none! I think a 'fuge of almost any size is a great addition...Go fo it!>
  Also, I have a thin layer (about 5 lbs) of sand from a very seasoned tank, plus 10 lbs of small, seasoned live rock and some Caulerpa.  Will this soup do it for me?
<Yep- I think it will be a nice way to "jump start" your refugium. Diversity is the key>
I will have a Gro-lux bulb over area, but if the down drain from my tank flows into refuge area, will that be to disruptive to plants/animals that are living there?  Suggestions are much appreciated.  Thanks, a 4 month newbie, and loving every minute.  
<I don't think that the influx from the tank will be too disruptive...Flow is important in a refugium, anyways. The "disruption" that you're trying to avoid is from predatory life forms. I hope that you enjoy some benefits from your little refugium! Good luck! Regards, Scott F>

Small Refugium With Big Potential (Pt. 2)
To:  Scott F. --Thanks for your timely replay to my questions of the other day.
<You're quite welcome>
I managed to hang my Turbo skimmer outside the refugium/sump, so that I could squeeze more space for the refugium portion, which I know is better--more is better, right?  Also, I was able to section off the influx from my down drain, added a few live rocks in that section with bubble baffles, and voila!  It actually works the way it should.
<Excellent!>
I was concerned about the rather thin sand layer, so I added more Aragonite over the live sand I had, and now the bed is about 4".  Should I make it thicker or is this sufficient??
<Well, tons of conflicting views here (what a surprise). I'd start with 4 inches and adjust if you feel that it is warranted>
BTW, the Red Sea Berlin turbo pump conked out on me at this time.  Would any 500-700 gph pump work, or do you think I need to get
another same item from Red Sea?
<If it were me, I'd probably stick with the "OEM" pump, and get another one from Red Sea>
Please suggest what you think would work, and thanks again for a very enlightening forum for this 4 month newbie.......Barry
<Our pleasure! Regards, Scott F>

Aquafuge pro
Dear Sirs,  I wrote earlier today w/ a question on flows for a 100 gal. reef tank which Anthony promptly answered. I have the greatest respect for your team and hold your opinions above all others,
<Thanks for the kind words!>
please do not misunderstand me but I've just recently ordered a $990 tank thinking I had a good handle on things, but now I'm wondering if I'm getting in over my head (no pun intended).
<Has happened to all of us.>
Basically Anthony answered that I need 10x the system flow thru the sump to keep it from getting stagnant.
<I am not sure what Anthony's exact comment was, but I am not sure that this was his intended interpretation.  10x water flow is ideal in the display.  10x would is also a good ideal for the sump, but that is 10x it's volume (~250gph min in the case of the Aquafuge pro).  Many systems are designed so that all of the display flow also goes through the sump, but in this case that may not be ideal.>
The sump is the Aquafuge Pro from CPR. I had e-mailed CPR earlier asking what pump they recommended and received a reply just a few minutes ago saying no more then 400 gph thru the sump, use a Rio 1700.
<This sounds like a reasonable recommendation based on the size of the product, although I would recommend a similarly rated Mag Drive, Sen, Sedra, or Eheim pump over the reportedly less reliable RIO.>
My dilemma is this: I have a very bad feeling that the tank builder is going to cut me short on the overflow capacity if I need 1000 gph for the sump alone.
<Indeed, a tank with overflows that can actually handle that kind of flow is rare (and often impractical).  This is largely why powerheads and closed loops are so commonly used.>
I'm also heeding Anthony's advice on no power heads. So if I go closed loop w/ a separate pump and run it from the sump I will also need overflow capacity for that.
<By definition, closed loop circulation does not pass through the sump.  Water is drawn directly from the tank, through the pump and back.  There are many design possibilities, and most do not require the use of a pre-existing drain.>
Before I go back to my LFS tomorrow and say hold everything the tanks gonna be wrong, I would like your feedback on this situation. I do not want to offend anyone, I do not want to offend CPR or take any credibility away from anyone, but as you can see I'm getting some conflicting info.
<Yes and no.  Sometimes it is hard to see the "big picture".  400gph through the aqua-fuge is a good recommendation.  1000gph total in your display is a good recommendation.  Since you can't move 1000gph through the 'fuge, you will have to make it up another way.  Which way is best depends on your budget, how badly you want to avoid powerheads and other details of your system and hardware.>
I want his tank to be right from the start, no band-aids or jury rigging if it can be avoided.
<Kudos on trying to plan well!  All to often we set things up just to get it done and then are stuck with poor choices.>
What would be the recommended size of overflow holes for 2000 gph
<You would probably need at least 3-4 1.5" drains to handle that kind of flow, which most folks would consider to be impractical.>
or more and what are your thoughts on CPR saying 400 gph thru the sump? Maybe I'm way off on the whole thing, should I run some other type of filtration?  Can it be that mud in a sump can't handle 1000 gph? I'm guessing the CPR system would run similar to the ecosystem are the flows that low for those? If you feel this note could cause some problems w/ CPR or whomever maybe it shouldn't be posted. I just want to have the best experience possible w/ this new adventure, but having some trouble w/ the foundation. Your the only ones I know that have the experience to provide and educated answer.  Respectfully, Sam Marrone
<I removed the reply from CPR since it wasn't really relevant to the discussion and they made a good recommendation that is already covered here.  My personal preference for a "typical" system with a refugium placed under the stand is to provide appropriate flow through the refugium (in this case 400gph) to the display with an appropriate pump.  A single 1-1.5" drain will handle this fine.  Then, apply a closed loop to provide the additionally flow desired to the display.  A second drain can be plumbed directly to the inlet of the circulation pump (drain hole must be submerged at all times, no sucking air!), and the return line plumbed as desired.  I hope I have explained all clearly and adequately.  Best of luck, and feel free to write back for clarification.  Adam>   

Re: Aquafuge pro, refugium flow and display flow 2/20/04
Adam, Thank you very much for taking the time to go over this, I guess I did do Anthony a slight injustice by misinterpreting 10X the sump vs. 10x the tank volume.
<Glad to, that's what we're here for!  No injustice at all.  There are many ways to skin this cat, and the best one depends on your circumstances.>
I'm no longer panicking I will let the tank be built as is and run 250-400gph thru the sump. Now as for the closed loop, which is what I will attempt, do I plumb an extra line in the overflow compartment and let that run to the input of the return pump thru a tee? I guess there are many options here, but does that make sense?
<This won't work.  The closed loop must be closed.  The inlet to the closed loop pump must come directly from the tank and return to the pump with no connection to the sump.  The most important reason is that the inlet must be submerged at all times and therefore will siphon if the pump stops, potentially flooding the sump.>
I've since replied but I'd like to rephrase my question, i.e. 100 gal. tank looking for 10-20x circulation, if 400gph goes thru the sump and I run a closed loop into the return pump inlet then I'm running approx 1000-2000gph thru one pump? This is starting to make some sense as 2000gph is a pretty big pump I could just run the closed loop on a dedicated smaller pump getting water thru a 2nd line in the overflow? Sorry for all the questions but I'm a complete novice to the sump/plumbing requirements in a sound system. Thanks again.  Sam
<My suggestion would be to choose a sump return pump that is rated to deliver the desired flow through your refugium.  Choose a second larger pump for the closed loop. Your closed loop will need it's own inlet/drain that will always be submerged.  You may have to use some creativity for the inlet and returns of your closed loop, but if you do a search on one of the popular message boards you will find lots of discussion.  You can also make a sketch and e-mail it here for feedback.  Keep in mind that since the closed loop is drawing the water from the same place it is returning it, there is negligible head loss.  Best Regards.  Adam>

- Sump/Refugium Design -
Hi guys, long time reader first time caller.  I'm new to the saltwater arena and after reading all the great information on your site I decided I wanted to hook up a refugium to my main 47 gallon bow front tank either 15 or 20 gallons, I made up this design for my system and was wondering what you thought I'm not sure on many of the specifics yet but do you think my idea is practical? <A couple of issues occur to me: first, I don't think the barrier/weir will be able to be at the height shown in your diagram - typically, sumps shouldn't be filled much more than half to make room for the transit volume in the plumbing and overflow water when the power is turned off. Second... is it your plan to pump water under the plenum? It seems that what is your diagram suggests, but if this is the case, it won't actually perform as a source of denitrification. Do consider having your water coming in from the top of the sump, with the plenum intact and undisturbed at the bottom of the sump.> Should I used the carbon insert or just scrap it and same with the bio balls? <You'll want to run carbon from time to time, but it easiest placed in a bag in a high flow area of the tank. The bio balls should be fine as long as they are submerged.> Thanks for your help I look forward to your response.
-Jeremy
<Cheers, J -- >

- Sump/Refugium Design, Follow-up -
Thanks a lot for your help I'll make sure to change my design, and not pump the water up through the sand. I read that was good to do at another site thanks for the correction. <It might be good to do, but it won't really be a 'plenum' as you had described. It would just be a sand filter, and likely a problematic one at that. No worries - I think the change in design will treat you right.
Cheers, J -- >

Refugium Size 2/17/04
I currently have a 120 gallon reef tank with clams and a few soft corals.  For fish, I have three dwarf angels, a yellow tang, a ocellaris clown, a Firefish goby, a Rainford goby and a scooter blenny. I am planning on adding a mandarin goby and a few more small ditherfish.  At night when I search my tank with a flashlight, I haven't noticed a whole lot of fauna crawling around (tanks been set-up for about six months), so am considering adding a refugium.  
<excellent! they are invaluable IMO>
Unfortunately, I don't have much room under my stand (taken up by the sump), so I am looking at a hang-on the back refugium (Aquafuge Hang-on Refugium--large).  However, according to my calculations, this model only has a volume of 7 gallons (25" x 4" by 12")-will seven gallons of refugium have a significant impact on the populations of 'pods/other desirable flora/fauna?  Thanks-your site is great.
<anything will be helpful... but these HOB style fuges are truly tiny. Ideally, a refugium should be 20-40% of the display tanks size. [public aquaria often use a 1:1 ratio!]. Do consider a refugium plumbed upstream (above) the tank on a shelf next to the display top (can be just slightly higher for an overflow hole to drain in to the display... see our book "Reef Invertebrates" by Calfo and Fenner for extensive coverage on this subject). Anthony>

Sump/refugium question on water flow 2/16/04
Dear Sirs, Thanks to all of you for your help in the past. Couldn't have had a successful marine setup w/ out your guidance.
<with hope for your continued success!>
I'm now ready to go reef and I've ordered a 100 gal.  tank w/ internal overflow. My LFS friends saw the CPR Aquafuge Pro refugium in use while attending  a  dealer show in Chicago. He was very impressed, enough to convince me to use this setup for the new reef tank.
<its small (too small) but still somewhat effective>
My existing setup does not employ a sump (one of the reasons I'm not constructing my own yet)  and I had  a few basic questions about flows.  From what I've read, a reef system should have 10-20 x  the water flow per hour.
<yes... and those wanting faster growth or with SPS corals and clams may need higher still. Paletta (2003) cites world class displays with as much as 40X>
I think this means movement in the tank not how much is being passed through filtration? Is that right?
<correct... a 100 gallon display tank needs a total of 2000 gph running through the display combined (powerheads, sump return, refugium overflow, etc... all total)>
If true, I have this sump which will be filled w/ mud passing a fraction of the 10-20x flow,
<mind you the sump needs around 10X so as not to get too stagnant/slow)>
now is the rest of the 10-20x  just water being circulated w/ powerheads or whatever?
<correct>
I want to start this system right but don't understand how much water has to be filtered per hour and how much just needs to be moved. My LFS has been  helpful but there seems to be a gray area on return pump size for the Aquafuge sump w/ mud. Any help is appreciated. Respectfully, Samuel J. Marrone
<the refugium flow is to be determined by what you'll keep... good Chaetomorpha or Gracilaria will need flow strong enough to keep them tumbling... Caulerpa can take slower flow. Do ID your fuge needs first, my friend. Anthony>

Sump/refugium size 2/17/04
Anthony, Thanks for the prompt reply, you know what I'm gonna ask next---its small (too small)........What do you recommend? I'm all ears. Thanks again, Sam
<refugiums of any size will be of some benefit... but do try for 20-40% of the display tank size for a noticeable impact [public aquaria often use a 1:1 ratio!]. Make a DIY one upstream or downstream... or look at the larger HOB style ones. We cover the topic of refugiums at great length in "Reef Invertebrates" by Calfo and Fenner. kindly, Anthony>

Unlit Refugium 2/14/04
Hello WWM Crew,
<howdy>
I am a week or so away from plumbing my new set-up which will include a 50 Rubbermaid stock tank plumbed upstream and gravity fed back to the display (120g).  The plan for this tank was for it to be used as an unlit refugium with LR and a shallow, med - large grain aragonite substrate.  Predator free, this tank's purpose would be to provide a safe haven for pods to live and breed while constantly supplying plankton to the display tank.  
<agreed with all of the above... although the addition of a dense matrix like scrubby pads, coarse polyester fiber pads/foam blocks... or living Chaetomorpha algae with light would provide a much better realm for the cultivation of microcrustaceans than  shallow gravel and LR>
Simply put, I want a mandarin fish someday and I want this refugium to supply it's food.  
<yes, do consider the above>
Is an unlit refugium the right environment for such plankton?  
<correct>
Would I be better off lighting the refuge?  
<nope... not necessarily. Although you need to delve/research deeper here... mandarins eat copepods and not large microcrustaceans like amphipods and mysids. Your coarse media is geared to growing the latter. For copepods, you need a supply of fine sand (deep at 5=") and source of phytoplankton>
I don't intend to use this for nutrient control and don't want to constantly prune algae.  
<understood and agreed>
By the way, does 300gph turn-over (through the refuge) sound good?
<not even remotely enough... you will struggle with algae problems in this and any tank with such low flow. 10X is a fair minimum for refugia. Towards 20X for display tanks for best results (even higher for SPS tanks)>
Thanks in Advance Mike
<kindly, Anthony>

Upgrade tank setup and move + water movement
Hello,
<Hiya! Scott F. here today!>
Your site is extremely helpful and a virtual Great Library of Babylon of
information.  I am only 6 months into the hobby and the recent find of your site has inspired me to expand.
<We're glad to be here for you!>
My question is about filtration concerning my new tank.  I currently have a 37 gallon eclipse and recently acquired a roughly 55 gallon tank
(50x16x17).  I have been reading on your site that live sand should not be
more than 1/2 inches or less than 3-4 inches.  All my LFS have told me that 1 to 1.5 inches is optimal so that the sand does not compact and that it would be adequate.  Can you explain in a bit more detail (I read on your
site, something about not deep enough to fully denitrify) why this is not a good amount of sand?  If I had a good amount of live rock (1.25 - 1.5
pounds per gallon) would having the 1.5 inches of sand not matter or would
it end up hurting the tank?
<Well, this is the conventional wisdom...A shallow sand bed may not be deep enough to foster complete denitrification, but too deep to be fully aerobic...A Potential problem. On the other hand, there are some studies that I've read recently that indicated that the denitrification processes occur in nature in the first inch or so of sand, implying that you get some of the same benefits from a shallow sand bed as you do from a deep sand bed...This warrants further review from the hobby before this controversy is resolved.>
I have also set up a 20 gallon sump/refugium under the tank that will be
only about half full (so making the aquarium actually about 65-67
gallons).  The refugium part is 15x12x11 area (roughly 8 gallons?).  I plan to grow plants (recommendations on plants?) in here and/or macro algae to help with filtration, should I put live sand in there or mud?  If live sand is acceptable for the plants, should I just make this area 4 inches or so?
<I'd go with Chaetomorpha, which does not need to be "planted">
If 3-4 inches is minimum in the main tank, that only leaves 13-14
inches of water depth.  I also have a Fluval 404 on the way but I'm
wondering if even need it or would it hurt the tank?
<Would not be harmful...Just replace the media regularly and keep prefilters clean...>
I was planning to send it back but I realize that I only really have a 6x6" area for mechanical filtration from the overflow and some chemical filtration via carbon.  I do not yet have a protein skimmer (any suggestions on which one to get for my tank, preferably one that fits in a 6x6" square area or that sits out of the water and can be plumbed in by going over the top edge of the sump?)
<Try an Aqua C Remora Pro...>
I don't plan on going full reef for at least another 5-6 months after I move my livestock over next month (as I plan to be out of the country for about a month over the summer plus I want to make sure the tank is better established and stable).  I just want to keep fish and some
inverts for the time being but no coral till later. I will begin cycling the tank this week (in which I plan to start cultivating live sand as well if I need a lot more) and plan to slowly move live rock over from my smaller tank after 2 weeks and begin moving  livestock over sometime in mid-late march (depending on ammonia levels etc.).  I will be using some of my old tank water (just by taking the water from my old tank as I do water changes to add into the new one.)  and live sand along with uncured live rock to help cycle as well as cultivate more live sand over the next month.  Is this a good idea?
<Sounds fine to me!>
One other topic, water movement:
My return line will be pumping out water at about 400-500 gph (I think,
including head) from the back corner of the tank facing the opposite
corner.  I also plan to use a PowerSweep 228 (270 gph) on the opposite side
facing laterally a few inches below the surface.  This is for the lateral
and turbulent flows. I will also be using a smaller PowerSweep 214 on the
return side (or the opposite side?  any suggestions?) as low as it can go
(without sucking things up) to help blow detritus and debris around off the
bottom of the tank.  This PowerSweep will be connected to a timer to go on
every 15 min. for 15 min. (ever 30 min at night) in an attempt to create a
surge effect (best I could think of without buying a wave maker or setting
up some big bulky noisy contraption).  Is this a good idea?  Too much
<Seems like you can never have too much flow! I would avoid timers on the powerheads, as most of them don't take kindly to being turned on and off repeatedly! Just run 'em 24/7>
little?  Baby Bear's just right?
<Sounds fine to me!>
Thank you so much for your help to beginners to the hobby such as myself!
P.S.
How important are water chillers?  I live in Southern California in the
greater Los Angeles area slightly above sea level. Temperatures average
around 95 to the hundreds in mid-summer days but also drop back down to he
60s at night.
<I live in LA, and I wouldn't be without my chiller...'Nuff said! BTW- what not check out the two excellent clubs we have in the So Cal area- Marine Aquarium Society of Los Angeles County (www.maslac.org) or Southern California Marine Aquarium Society (www.scmas.org)...Enjoy! Regards, Scott F>
"It is in vain to expect our prayers to be heard, if we do not
strive as well as pray." - Aesop

Producing nitrates to feed macroalgae? 2/12/04
I have a question that I really need help understanding. It seems to me that having bio balls before a algae refugium would be very helpful. From what I understand plants will only absorbed nitrate when ammonia and nitrite are not present, as it prefers to absorb these first. Since there are many things in your system that can break down ammonia and nitrite wouldn't it be best to have the plants absorbing as much nitrate as possible as it is the hardest to break down?
<flawed theory: the nitrate being produced is being done so by a man-made filter. Bypass the problem by aggressive skimming of organics before they turn into nitrate... and/or maintain adequate water flow so that live rock, live sand fauna and invertebrates consume the matter directly rather than letting it go through nitrification. This boils down to natural filtration versus artificial filtration methodologies>
Since the bioballs have been accused of being overly efficient in breaking down ammonia and nitrite wouldn't they create a situation where the plants would have to feed on nitrate and you would get maximum absorption of that nutrient (which is the hardest to get rid of) out of your plants.
<it's haphazard and unquantified. How much nitrate will be produced, how many plants are needed to temper it, what is the rate-limiting factor if not nitrate?>
I thought this was why ecosystem has always kept them in there design, even though they are submerged? Thanks
<Hmmm.. I cannot comment here. I do not care for or subscribe to the ecosystem methodology wholly. I appreciate some components of it, but would not employ it personally as directed (with Caulerpa, overpriced mud, etc). Anthony>

-Refugium lighting-
Hi, What would you recommend (lighting (what wattage/type?) for my 6" DSB with some Chaetomorpha.  The sump is 20"Lx16"Wx18"H and situated underneath the display tank. <A few 18" NO lamps would get the stuff to grow, but you'd experience much faster growth under more lighting (i.e. PowerCompacts).> Would you recommend putting some of the Chaeto in the display tank or not. <Well, since it doesn't attach to anything, you'll have to wedge it in some crevices and deal with it when it starts blowing around the tank.> I currently have a FOWLR and some mushrooms, green star polyps, and a candy cane coral. <Not a FOWLR anymore!> The lighting for my 60 gallon is 4x65 PC's <I hope this helps, -Kevin>
Thanks again.

Sump/refugium/deep sand bed - confusion
I have been reading many of your FAQs and doing a lot of internet
research over the past couple of months.
<Research is the best thing anyone can do for a reef tank.  Kudos for taking the time to look it all over.>
We set up our FOWLR tank 15 months ago and are now wanting to upgrade to a reef tank.  
Current setup:
77 gal AGA
Fluval 404 canister filter
Seaclone skimmer
4x96W fluorescent light
2 powerheads
approx. 30 lbs live rock
2" live sand/crushed coral bed
<Well, the Seaclone skimmers aren't the best on the market, but it does get the job done.  If you are going to do light loving corals and things like clams you will need some lights that are much more powerful than that.  Check out of the Lighting section on Wetwebmedia.com to learn more about what sort of lighting you will need for the corals you wish to keep.  I myself like a bit more live rock in my tank, one to two pounds per gallon.  But that is all up to personal taste.  If you feel that 30lbs is enough then that sounds fine.  As for the sand bed, With larger tanks many reefers are finding Deep Sand Beds to be very beneficial to the overall well being of their tank.  I myself use sand beds, and skip the crushed coral.  My findings were that large crushed coral has lots of dead spaces for food and waste to rot in.  The sugar grain sized sand in my tank not only looks nice it also offers a low oxygen area for the beneficial bacteria to break down the ammonia.>
What I would like to do is get rid of the filter and plumb in a sump so that skimmer and heater etc. can be hidden.  
<Very good plan, tank looks so much more natural without all the extra stuff hanging in the tank.>
I understand from your site that the Seaclone skimmer isn't very effective and plan to buy a new one (am thinking about the Aqua C EV180).
<A nice skimmer, a friend purchased one recently and he hasn't had any complaints.>
First question - is the 4x96 light strip going to be ok to keep low to med light corals (tank is 20" deep)?  
<Depending on the bulbs you use, and how often you replace them then there are a some low light corals and mushrooms that would do quite well in lighting like that.  Other corals you might need to feed more often to balance of the amount of light.>
I also plan to add 40-50 lbs additional live rock and create a 4" DSB in the main tank. My purposes for this would be NNR and phosphate reduction.
<This is why it pays for me to read the emails prior to answering them.  I had addressed the issues above.  More rock is good, and DSB are great!>
    I am currently battling a hair algae problem which I am
fairly certain is due to high PO4 due to a lazy maintenance schedule (nitrite is 0 and nitrate less than 10).
<Getting a bit lazy with tanks will lead to some outbreaks of some weird stuff.  Luckily it was hair algae, which can be eaten by many clean up critters (Turbo snails being a big one).
I did a 40% water change 2 weeks ago, and another 25% change last week and plan to continue on a 5-10% weekly water change using RO/DI water.
<Good plan.>
  My test kit only does PH/Ammonia/Nitrite/Nitrate but plan to buy a better kit.
<having a better kit will definitely assure that you will know much more about your tanks well being.  For corals you will want to know the Calcium and Alkalinity levels.>
I am confused as to how to accomplish NNR - so much conflicting advice.
<Simply put, by having a deep enough sand bed, which should be around 5 inches, you will have a low oxygen area and should offer a great area for the bacteria to grow and do their work.  There are a few good articles in our articles section here on WetWebMedia.  And I also suggest checking out the Forums here as well.  You will meet a few folks that really know there stuff about NNR.>
Does what I am planning sound workable?  
<To me it sounds quite workable.  I've known people have impressive reef tanks with much less.>
I don't have much space under the tank and want components hidden as tank is in living room, so would have to pick either a sump or a refugium.  I am leaning towards a sump as the refugium would never be seen under there and I would have to find yet another outlet to plug a light into.  Basically I need a simple but effective filtration method.  I plan to keep my current tank inhabitants (lawnmower blenny, firefish goby, blue damsel, 2 BBT anemones, blue band goby, and canary wrasse) and add some corals like torch coral, mushroom, xenia, easier LPS.
<Bubble Tip Anemones are more delicate than any of the other corals you will be adding to this tank.  I would do some research into what they need in order to thrive.  Anemones really don't have a great track record in people's tanks.  In fact somewhere between 80-90% of Anemones imported in die in home aquariums due to poor tank conditions.>
Do I need a refugium in addition to a DSB for effective filtration?
<Adding a refugium will be beneficial to the tank in general.  It's not a needed thing in the grand scheme of things with use with DSBs.  But, a refugium will over a larger volume of water, since the depth of the sand bed will remove the effective water volume from the tank.>
Thanks for any advice you can offer.
Barbara Ottley
<Hope that helps.  Good luck, and keep up the research.  I suggest you also look at getting the book "The conscientious Marine Aquarist" by Robert Fenner.  It's a great book and will give you a great deal of knowledge of the subject. -Magnus>

Refugium Questions
I greatly appreciate all the wonderful information on your site. I have two questions:
<Hi Scott, Adam here. Glad you have found good info on WWM!>
1. I'm considering stocking my refugium with small clams. I have a 175 watt MH light that hangs over the refugium. How does a small 2-3" clam stack up against macroalgae in terms of nitrate removal? Should I just stick with macroalgae?
<If the goal is nitrate removal, then a deep static sand bed will provide the most benefit. Macros will work too, because of fast growth, but IMO are much more important in terms of phosphate and metal removal.>
2. Everyone seems to advocate a very slow rate of water movement through a refugium. This is puzzling to me. The reason offered is always that the macroalgae needs time to "catch" the nitrates. (Yet I never hear that corals need time to "catch" calcium or iodine or whatever.)
<This is total nonsense and demonstrates a poor knowledge of uptake/exchange processes. In this regard (ignoring practical concerns) more flow is better because it delivers more nutrients to the algae.>
Is nitrate fundamentally different from other dissolved substances?
<Nope.>
My experience has always been that like corals some macroalgae prefer a lot of water movement and some don't. My refugium is between my sump and the return pump and has a lot of water flowing through it. The macroalgae seems to grow fine.
<Totally agreed. As a general rule, if you aren't kicking up sand and the algae stay in place, it should be fine.>
Will slowing down the water movement actually increase macroalgae growth? In other words - does water movement through a refugium have any effect on macroalgae growth - except to favor those macroalgae that seem to like more water movement?
<Quite the opposite. If you slow down the water movement (past a certain point), you will limit the nutrients available to the macro algae.  Thank you for your help! Scott Campbell
<Glad to! Adam>

Reverse daylight question 1/28/04
Hi guys, Thanks again for all the useful info.
<Always a pleasure!  Adam here today, BTW.>
My question is on my refugium I am setting up.  I am setting up a display refugium that will sit next to my 75 gallon display.  Water is being fed from my sump to the refuge and back to the sump.  I have had a 20 gallon high drilled with 3 holes and bulkheads on the back and on the top.  2 - 1" for overflow and 1 - 1" for the return.  I have 60 lbs of Natures Ocean "Live" sand for my substrate.  I did not buy this overpriced stuff for any other reason than this refuge is being hooked up to a tank that has been running fine for years and I did not want to have a sand storm for days waiting for things to settle.  So I spent the money for "clean" sand.
<Sounds like a nice set up.>
Anyway my main question today is on my lighting.  I want to have macros and some LR in the refuge for nutrient export and food for my tank.  I have read allot about the benefits of running my lights on a reverse cycle from the main display.  I will have a PC unit I believe it is called Moonlight lamp.  It has 2 - 65 watt PC bulbs and two Moonlight bulbs.  Since this tank is in my office at work and located next to my display with it's 2 - 175 watt 14K MH and 2 - 40 watt 50/50 actinic / daylights it will never be dark during the day in the refuge.  Does this overflow of light cause problems that I should be concerned about.  I could possibly create a dark "boundary" between the two tanks however, room light etc will still be an issue.  Obviously, I may be worrying to much about this but in my quest to not have problems I figured I would ask the pro's... Thanks, Dave Thanks and have a great day!
<I don't think you will have any problems.  I would recommend Chaetomorpha over Caulerpa for a wide variety of reasons including the fact that it doesn't crash, it makes better habitat, and it doesn't produce as many toxic metabolites.  If you are concerned, paints designed for glass are available.  Painting all sides but the front viewing panel will help keep out extraneous light.  Best Regards.  Adam>

Sump/Refugium Questions (1/22/04)
   I am a new reef hobbyist. I had fish only tanks many tears <You probably mean years, but many hobbyists have shed plenty of tears over the years.> ago and boy have things changed. <Yes indeed.> I am in the process of starting up a 75G reef. The reef will be mixed livestock and corals and I would also like a clam or two in the future. 
<Probably only one in that small tank. They get huge.>
   I have a Rubbermaid tub that I am using as a sump for now. I am going to build a sump soon. I have been reading "Reef invertebrates" and would like to build and use a 'fuge. I have a few questions. I think I want to keep the 'fuge and the sump separate. <OK>
   So I'm looking to pump water from the first stage of my sump into the 'fuge and them back out into the last stage (Water that has been run through my Protein skimmer). Is this a good way to get the water into the 'fuge before it runs through the PS? <An overflow from the refugium into the sump is better. See the first link below for a good diagram. Mine was made by a local shop and is all in one tank with a toothed divider between the two chambers allowing overflow from the refugium part to the sump, which contains the heaters & skimmer.>
   I am also somewhat unclear as to what type of 'fuge to use. 1) Live rock and DSB. 2) Macroalgae 3) A combination. <My favorite> If I try to do a combination do I mix the Macroalgae and the DSB/LR in one chamber or do it in 2 chambers? <Can be done in one if not too much flow that disturbs the sand.> Any directions along this line would be very helpful. I haven't been able to locate any pictures or directions from the web. So any links to that end would
be helpful. <Try here:  http://www.inlandreef.com/Images/DIY/Plumbing/refugium_plumb.gif  and here: http://www.ozreef.org/>
Thanking you in advance for any input. Jordan <Hope this helps, Steve Allen>

- Refugium Methodology -
Hi Crew,
I have spent hours (possibly days) reading through all the information regarding refugiums and plenum on WetWebMedia and various other sources.  It seems that, just as I think I have decided upon my design, I find other conflicting information so I am hoping to get your input.
The refugium I am constructing is a 20g tall aquarium in the base of my 180g stand (space limitations).  My purposes for adding the refugium are: NNR, phosphate reduction (current diatom problem on glass) and to provide food sources for a mandarin and for my tangs (‘pods and macro algae).
My plan was to add a plenum to the bottom of the refugium and to use 4”-6” of aragonite sand for a substrate, adding something similar to “Miracle Mud” to the top layer of the substrate.  One person commented: “You don’t need a plenum and a DSB, choose one or the other. <I'd agree with that.> Otherwise, they will compete and deplete the system of enough nitrates/phosphates to support coralline. <Don't know if I'd agree with that.> A refugium has a mud substrate for growing plants.  If you use sand, this is not a refugium. <Refugium is actually a catch-all term, and has next to nothing to do with the substrate or depth of same to make it a 'refuge'.> You should just use a plenum as they are about 10X faster at removing nitrates.”  Another person commented: “Why are you using a plenum in a DSB?  You should eliminate the plenum and just use the DSB.” Still others (in fact, one WWM crew response indicated: “Why not get the advantages of using both a plenum and a DSB?” <Interesting... doubt that was me.>
Of course I realize there will continue to be disagreement but what are your views on the above opinions? <I think a refugium will be whatever you want it to be. Substrate depth, plenum or not... these things matter only a little. Having a box with water in it and a lack of predators will create a refugium. Solving NNR issues and the like are a separate issue from the refugium - the deep sand bed for instance will likely have more affect in the main tank as it will have more surface area, but it will have some affect in a refugium. Same goes for a plenum, although less practical in the main tank if you have burrowing fish.> Will the use of a plenum/DSB refugium inhibit coralline growth? <Not in my opinion.> Would a mud-type addition (i.e. “Miracle Mud”, “Funky Old Reef Mud”, etc.) to the top layer of sand not be beneficial for growing ‘pods and mangrove, Caulerpa or other macro algae? <No... this will happen with or without the mud. Mud typically has other benefits more relevant to water chemistry.> What are the best plants to grow for NNR and for tang food? <Whatever you can get your hands on that the tangs will eat.> Should “janitors” be added to the refugium to reduce detritus or will they just reduce the ‘pod population? <No... it would be much of a refuge then.>
Thank you for providing some clarification,  --Greg
<Cheers, J -- >

- Refugium Methodology, Follow-up -
Thank you for the prompt response! <My pleasure.> I would like to just get clarification on a few responses.  You said you agree with not using both a plenum and a DSB in a refugium.  Which do you prefer and why? <Refugium - easier to get going and maintain.> Do you agree with the comment that plenums are 10x faster than DSBs at removing nitrates? <Not without some proviso, no I wouldn't agree with that.> So far, comments I have received are similar to "they are not both needed" or "there might be some benefit to having both but not likely".  So it sounds like there might not be specific benefits for having both but I have not heard of any significant drawbacks to having a plenum and a DSB.  If there is possibly (or possibly not) something to gain but nothing to lose from trying a plenum and a DSB in the refugium, I think I will try both. <Please, be my guest.> As you said, the surface area in a 20g refugium is limited (when comparing to the attached 180g tank) so my though it I need the most efficient method of NNR possible -- why not take advantage of both methods? <Why not build a larger refugium - I will say again, it's too small, even if you use both methods and a third no one has ever heard of, I don't think this will produce a useful amount of nitrate reduction.>
FYI: I found the WWM article I mentioned -- regarding taking advantage of both a plenum and DSB.  It was Bob Fenner who had this response (maybe I took it out of context?):
"Will a plenum sump or a Caulerpa refugium be "better" for lowering nitrates?
<Overall... the Caulerpa if you had to choose... you don't have to... you can/could have both in the same sump...>" (http://www.wetwebmedia.com/PlenumFAQs.htm) <Last time I checked, I was allowed to have my own opinions on such matters - you as well.>
To answer my previous question about adding "janitors" to the refugium (keeping sand stirred / detritus minimized), you responded: "No... it would be much of a refuge then."  Were you saying "janitors" would be predators of 'pods, therefore this would not offer much of a refuge for the 'pods or were you saying it *would* be much of a refuge for both? <Sorry - looks like the contraction got left out - it WOULD NOT be much of a refugium.>
Thanks again!
--Greg
<Cheers, J -- >

Lighting Chaetomorpha (1/22/04)
   Hi, and thank you for your good work !! <A pleasure>
   I'm searching for a couple of days on the web what is the amount of light (in lumens) the Chaetomorpha algae do need and how many hours/days at most can we light it?  <Don't know how many lumens. Standard output or PC fluorescent lights should be fine. I light mine with 46W of PC. W would not recommend more than 12 hours per day.> Is it the best choice of algae to put in a refugium with a deep sand bed  and to do nutrient export ?! <A matter of opinion. There are pros/cons to all algae. Read the FAQs on Chaeto & Caulerpa and choose which is best for you.> Thank you ! Steve Timmons  <Hope this helps. Steve Allen>   

New Tank Advice
Hi Mr. Fenner,
I heard that I missed your visit to Milpitas CA. Aquatic Gallery.  My brother has gotten me back into the world of fish. He told me to buy and read your book "The Conscientious Marine Aquarist".  I have been enjoying it (kids and wife are beginning to feel the effect of daddy getting into something other then them!).  I have attached a picture of how my system will be set-up and would like your input/thoughts.  This tank will house fish and Live Rock only (maybe after one year I may start buying corals).  The display is a 125gal plexi. My plan is to have the sump 14.5"L x 18"W x 20"H house the protein skimmer and the return pump.  The return pump will have a valve to split the water being returned to the tank with water (about 100gph) to the refugium. Refugium is 23"L x 18"W x 17"H. I'm not sure if I should buy an 1800gph pump or a 1200gph pump!?
<Either will do... you won't get the actual stated flow-rate... due to head pressure, other influences.... If in doubt at all, I would go with the larger unit>
A few questions:
1) The LFS told me that a refugium is a bad idea for a fish and live rock only tank and that I would be dealing with a lot of dead fish!
<Umm, no. Not the case. Take a look at our website: www.WetWebMedia.com and if you can find a copy, Anthony Calfo's and my Natural Marine Aquariums: Reef Invertebrates book... there is extensive coverage of refugiums there>
I can't believe what he is saying is true. Is this correct?
<No my friend>
2) If a refugium is (and I believe that it is) a good method and will work with LR and Fish only - I plan on having a 4" bed of sand and some
live rock, what types of plants would you suggest I put into it?
<Please see WWM here>
3) Should I have more then 100ph pumping through the refugium? I thought that water should travel slow through a refugium but it seems as I have been reading in WWM that the turn rate should be 10 times the volume!
<Best to have 2,3 times turnover an hour or so...>
Last question Mr. Fenner. Should I run a dedicated powerhead from the sump to the refugium?
<Not necessarily. The split flow from your main, recirculation pump should be fine>
Any advise and or thoughts will be greatly appreciated!
Kind regards.  Kevin.
<Enjoy, keep studying, learning, sharing. Bob Fenner>

- Refugium Considerations -
Hi Folks,
I have recently added a 100l refugium to my reef tank. The refugium is underneath the main tank, taking a feed from an overflow box; unfortunately a drilled solution will have to wait until my next display tank upgrade. I have set the display tank and refugium water levels such that flooding is unlikely. The return powerhead is controlled by a float switch so that the pump turns off if the overflow box fails. Not ideal plumbing, but certainly better than not having a refugium at all.
The refugium has a 6 inch deep sand bed, strong T5 lighting, growing Caulerpa. The supply of algae to the UK is appalling, so Caulerpa was my only option. I understand the regime necessary to limit the likelihood of the algae going "sexual". The purpose of the refugium is to grow critters for my mandarin to eat, raise pH overnight and export nutrients away from the System.
Water movement through the refugium is determined by the "return" powerhead, which pumps approximately 3,000l per hour (30x the volume of the refugium per hour). Most of the water movement occurs towards the surface, with considerably less at sand level. I thought it would be useful for the refugium to have it own local water circulation, as well as that coming from the "return" powerhead. This would increase water movement at sand level AND provide movement should the overflow box fail for any reason. Worst case scenario, I go away for a weekend and the overflow stops working, it could be 48 hours before I get home to restart the circulation. Local movement would prevent the refugium water going stagnant. Am I right in thinking some local movement would be beneficial, or am I taking the circulation too far? <I think you're on the right path.>
Assuming you do agree, I would prefer to use an airstone to move the water, rather than a "critter chopping" powerhead. I know I am using a powerhead to return the water to the main tank, but critters are only likely to make that journey once! On the other hand critters could pass through a local circulation powerhead countless times - I have this mental picture of a food blender for some reason! Are there any reasons why I should not use an airstone in this way? <None that I can think of.> For example, would it impact upon the growth of the algae? <Don't think so.> The refugium is home to the calcium reactor, so a small amount of CO2 may be present in the water, which would get chased out by the airstone. I can't make up my mind whether this is a good thing or not? I am assuming the algae would love the CO2, but on the other hand my slightly low System pH would benefit from CO2 elimination. <Chances are best that if the lights in the refugium are on, the CO2 will be consumed by the algae.> On balance, do you think "circulation by airstone" is a good idea or not, in my refugium? <It's not a bad idea - I can't think of pros/cons either way. I say go for it.>
Final question, about my filtration. The 350l display tank is filtered by 60kg of live rock, a Deltec MCE600 skimmer (wonderful unit - astonishing performance!), 25mg/hour of ozone injected into the skimmer, Rowaphos, carbon (changed weekly), 8% water change per week, floss in refugiums sump section (changed weekly). Before the refugium was added the display tank used a UV filter. By the time my fish are fully grown stocking levels will be heavy, but sustainable, for a reef. New additions of fish or inverts are now rare events, hence opportunity to introduce disease into the environment is low (I do quarantine as well). Should I leave the UV on the display tank to reduce any free floating pathogens, or should I leave it off the System to fully benefits from all the life produced by the refugium? <I'd leave it off. There is anecdotal evidence that systems that have been UV filtered for long periods of time begin to show an acquired immune deficiency problem, where the fish break down after years. Think there is likely some useful stuff being killed in the UV along with potential harmful stuff. I say can the thing and rely on good quarantine - perhaps run the UV on your quarantine system... is what I do.>
As always, thank you very much for your time. Your help is genuinely appreciated.  Andrew
<Cheers, J -- >

Refugium Volume
Hi all, <Hello, Ryan with you>
I'm new to this site and have done a lot of reading but haven't found a direct answer to my question. I'm setting up a new tank. It's going to be a 125Gal. Fish and Live rock only (at this point). <Great>
Below the tank I will have my sump on the left with skimmer and on the right a refugium. <Wonderful>
Because of size limitations, both the sump and the refugium will each be 14.5"L x 18 W x 16 H.
Is the refugium going to be too small for this tank? <No, not too small to be effective.  Any area free from the mouths of predators will be beneficial to your system.  Bigger the better, though>
I could (if I have to) put a larger refugium tank in the middle section of my tank, 28"L x 18 W x 16H.
<We're not talking a huge amount of volume increase here, so skip it.  I generally encourage refugium volume to be somewhere between 25%-75% of their display.  Even so, many aquarists have seen great benefits from a small, hang on refugium.  Good luck! Ryan>
This is an awesome site!  Thanks in advance.  I look forward to hearing from you!  Kevin Gagnon.

Tank Yikes!  Remote Refugium? (And My Bad)
>You said I could sell my large fish at LFS.  I don't know what that is. If you typed in www.lfs.com, would you get it?
>>Oh no!  My bad, Cheryl!  "LFS" is net-speak for local fish shop/store.
>Also, I don't understand the remote refugium. How does that work if it isn't hanging on your tank? Where do you get them?
Thanks, Cheryl
>>Refugia have only more recently been made more convenient by manufacturers offering hang-on-tank models.  You can make one yourself using a simple tub, properly plumbed, and pumped.  Search our site (our Google bar) for MUCH information on them.  Locating remotely means that it's not attached to the tank, thereby adding weight to one spot.  I know one fellow whose 'fuge is under his house!  Sorry again for the confusion.  Marina

Display refugiums
Hi Guys,
<Hi Dave!  Adam here.>
Enjoy your site.  Been a reef keeper for 18 years, and have been through the natural progression of ups and downs with my tanks.  I presently have a lightly stocked 75 gallon reef that is about 5 years old.  It has about 75-80 lbs of live rock that is encrusted with coralline algae and about 1 inch of sand on the bottom of the tank.  I run an empty sump and run a skimmer occasionally as my only filtration. I am looking to add a display refugium.  I have a 2o gallon high that I have had drilled in the back at the top for 2 drains and 1 return line.  Because of my space requirements I have to put it next to the display tank and want to make it interesting to look at as an additional display.  My question is this.  How much and what type of sand.  How much and what type of Macro?  What type of lighting?  And finally since I am adding this to an excising systems do I have to worry about cycling etc...?
<I would suggest about 6" of "sugar fine" aragonite sand, 8" if you can stand it.  In addition to short term settling, the low pH of the deep bed will dissolve as much as 20% of the bed a year.  You only need a small amount of macro algae to start.  They will grow quickly.  My strong favorite is Chaetomorpha.  It grows fast, is attractive, makes good habitat for pods and compared to Caulerpa is fairly non-toxic.  Lighting is easy.  Anything from two NO fluorescents up to a couple of PC's.  Anything more is overkill.  Cycling will not be a concern.>
Thanks and keep up the good work.  Dave O'Brien
<Glad to be of help!  Please let us know if you have any more questions.  Adam>

I Just Wasted My Money - 'Fuge Question
Hello
I have a refugium that I want to set up to an existing tank. I bought some Mineral mud and macro media that CaribSea sells as a set. Well it says on the package to let sit for 2 days before turning on pumps and then let tank cycle which tells me I just wasted my money. Can I rinse this?? <Probably not.> Will it hurt the tank to let it cloud up and clear up eventually??. <Don't think it will 'hurt' anything but some portion of your substrate will end up in your filters. I'm guessing the stuff is powder-fine.> And if I am outta luck with this stuff what do you recommend for me to use to add a refugium sump to an existing reef tank?? <Just fill the thing and let it sit, as the instructions suggest. Get it running for real in a couple of days and all will be fine.>
Joe
<Cheers, J -- >

Getting 'pods from Refugium to Tank (1/13/2004)
Hi Crew, <Steve Allen tonight>
I am planning a 20 gallon plenum / refugium for my 180 gallon aquarium.  <Why put a plenum in your refugium? A simple DSB should work fine.> One of my goals is to produce enough 'pods to support a dragonette.  <Can you make the refugium any bigger?> Can you suggest any way to encourage / accelerate these little creatures leaving the refugium? <Good question.> I will be flowing only about 100-150 gph of water through the refugium and I have a small (1/2" I.D.) overflow for the refugium water to return to my sump.
With this small flow rate <Plenty for a refugium of this size.> and only surface water being returned to my main tank, I am just concerned that very few 'pods will find their way to the overflow to escape the refugium.  Do you think this will be an issue?  <A valid issue. It may not be that many who get up there.> I had considered adding something like a small "ramp" than leads from the refugium substrate to the overflow opening but I do not know if this would have any effect in directing the 'pods. <A pile of live rock might work better.>
Oh I do have one more question:  Plenum plans on WetWebMedia.com call for a coarser bottom substrate layer than that of the top layer.  I noticed that the plenum plans on www.garf.org call for the same substrate on both layers.  Does having a more coarse bottom substrate make a significant difference in plenum operation?  I am considering using "GARF Grunge" for the bottom plenum layer since it is a very coarse material and it contains such a diversity of life and coralline seedings.  Do you think this is a worthwhile idea or would the microfauna in the "Grunge" just end-up dying due to lack of oxygen in the lower plenum layer? <Covering it with something finer will likely suffocate the fauna in it.> Maybe the "Grunge" would be better suited for the top plenum layer?  <I would think so.> Would the coralline present in the refugium "Grunge" seed additional coralline in my main tank? <May eventually spread. As far as a plenum goes, I favor the sugar-fine aragonite DSB of 4-6" in a refugium. No plenum. You could wind up with sand blowing everywhere with the flow rate you plan. If need be, a 1/2 inch layer of a coarser sand on top will hold it down better.>
Ok, so that was more than "one more question"...<Believe me, as a pediatrician, I am quite familiar with "just one more question..."> but thank you for all the great advice; I owe much of my saltwater success to the great people at WetWebMedia who answer my endless questions! <Me too> --Greg

Refugium Bubbles Causing Troubles!
Hi. Good day Mr. Fenner and Crew.
<Hi there! Scott F. with you today!>
I have an above-the-tank 10G refugium tank.  It’s about 2feet higher from the top of my 36G Tank to the left.  I’m currently using a Maxi-jet 1200 to pump water up and gravity feed down back to my 36G.  Both hoses are 5/8 OD. The problem is, as water comes down from the 10G, it collects air with it and makes lots of noises and bubbles in my 36G tank. How do I stop these noises and bubbles from returning into my 36G tank??  I tried a weaker pump, Maxi-jet 400, w/ the same problem. The bulkhead on my 10G is 1inch in diameter w/ a 90 degree elbow down.  PLEASE HELP!!!!
Thank you! -don
<Well, Don- it's gonna take some experimenting. A friend of mine who had a similar problem used a length of pipe attached to the return that ran all the way into the water (below the water line)...No more bubbles! Another idea would to be to direct the water over a piece of rock above the waterline, to "deflect" the flow a bit, although this may not work well. Try the length of pipe and see if that does the trick...>
Ps.  Also Currently purchased a Flame Angel. He's not eating and always hiding behind the LR.  What kind of food  can I introduce to him to get him started??
<Flames are omnivorous, so you can tempt him with a few different things. You might want to try a nice piece of live rock covered in algae growth, so that he can "graze" at his leisure. Alternatively, you could try some frozen Mysis, which seem to have a "smell" that fish find hard to resist. Some people try live brine shrimp, but I tend not to use them. Whatever food you try, don't give up. These are hardy fish that if well-acclimated and healthy, should eventually eat well. Good luck! Regards, Scott F>

- Coral in the FOWLR, More Follow-up -
Hi and thanks for the quick response on my questions, I really appreciate it.  In regards to my sump/refugium, the order of water flow will be the following: Do you have any recommendations that I should consider. <Not really, your sump layout is pretty standard... works well.> I am planning on buying the PC's as you recommended and I will have a couple of reef safe fish (1-Fairy wrasse, 2-percula clowns, 1-royal gamma). I currently have a 90 gal with Live Rock.  If there is additional info you might need, please let me know and I will reply.  Thanks again for all your hard work and assistance,
Jose

   H20                  H20
In to Sump    Out to Display Tank

X    X
X X X    X                                  
X X X    X
X 1 X 2 X    3   X
X  (Skimmer) X         (REFUGIUM) X (Pump) X
X X X    X
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Baffle 1:  Protein Skimmer (Euroreef CS6-1)
Baffle 2:  Refugium
My refugium will consist of an eggcrate (1 inch off the floor) with 2" of Coarse Sand followed by a screen followed by a bed of 2" fine sand (aragonite) and maybe some small fragments of live rock on top of that. <Are you sure your sump will be deep enough to accommodate this sand bed - methinks your water level will be very close and low to the sand bed once the system is running.> Should I consider adding a some type of light or small burrowing animals/bacteria/make live sand? <Not at the outset... let it come into its own and decide later if you want to add vegetation.  The entire surface area of the refugium is 1.5' by 1.5'. The reason why I am doing the refugium is for Denitrification. <Understood.>
Baffle 3:  Return pump to display tank
<Cheers, J -- >

- Planning Livestock and Refugium for New Tank -
Hello All,
It has been a while since I last wrote to you guys, however, I do frequent the Wet Web Media chat forums and find a bunch of useful information there.
I am in the process of re doing a 125 gallon tank w/dual overflows (each hole is about 1.75 inches) and had a few questions about the sump/refugium (used to supply the main tank with home grown goodies) that I wanted to install under the tank.  The inhabitants of the tank are going to be 2 Ocellaris Clownfish, one Purple Tang, one Royal Gramma Basslet, one neon blue goby, and one reef safe wrasse.  I saw what was labeled a "Christmas Wrasse" at one of the LFS but have been unable to nail down the image on any of the fish websites.  I have found something close but not exactly what I saw in the store. <Most likely a Thalassoma species of wrasse - more on these here:
http://www.wetwebmedia.com/thalassoma.htm >
I will also be keeping a couple of cleaner shrimp, a few snails, mushrooms, xenia, and a few LPS. <The shrimp won't last long around a Christmas Wrasse.> My lighting will be 4-96W PC.  I currently have about 120 lbs of live rock (various origins) curing in a Rubbermaid tub.  I have about 18 bags of south down sand to use in either the display or in the refugium (would a DSB in both be overkill?). <Both would be fine, but will cut into your water volume in the sump.>  I was looking at implementing the Return Manifold as suggested by Anthony Calfo. Is it possible to use this manifold with a fuge? <Don't see why not.> All the information that I found in the Q&A was about using it with a sump. <In either case, you still need a pump to move the water out of the 'container' and back up to the main tank. Refugiums are just glorified sumps when positioned below the tank.> Also I was thinking about using a standard 55 gallon tank as the sump/fuge.  I have read that if the sump/fuge was too narrow it would not allow the water enough area to slow down and render the fuge useless.  Would this be too narrow to use as a sump/fuge. <Don't think so.> There would also be an Aqua C skimmer and a Supreme return pump in the sump.  This would leave approximately 24"X12" for the actual refugium. <Think this will work well.> Any comments/suggestions are greatly appreciated.   
Jeff
<Cheers, J -- >

Lighting the 'Fuge
>Hi guys,
>>Hello.
>Have a question on lighting for growing macroalgae in my sump (refugium?).  
>>A sump should need no lighting.. eh?
>My sump is a 20 gal. aquarium. Next to the AquaC EV skimmer, PVC in line, and inlet return line there is very little room leftover. After reading many times on your website about the benefits of having liverock/Caulerpas in your sump, I'd like to try it.
>>Sounds good!  Do check out places like Inland Aquatics for other options in macroalgae, too.
>I saw a light that's 4 1/2 x 9  called a "mini might double'. It has a 9 watt 6700k and a 9 watt actinic described as 9 watt super PL lamps. Do you know if this fixture if left on all day would be strong enough to grow Caulerpa in my sump?
>>Hhhmm.. the important thing here is not only color temperature (the 6700K indicates color temperature in relation to sunlight, IIRC it's about 5,000K (Kelvin)), but also the lumens, or light intensity.  My own guess is that it would be sufficient if not placed too far away from the water's surface.  I managed just fine having Caulerpa inhabiting 1/3 of my reef tank, and that was at one end, under normal output fluorescents.  
>By the way the place where I would have to put this would be fairly turbulent. Thanks again for your input/advice/expertise. Kevin
>>Turbulence shouldn't cause any problems other than if a lot of water might be splashed onto the fixture itself, in which case you must take precautions to protect it, and be sure to use a GFCI (ground fault circuit interrupter).  Marina

Refugium (macroalgae) Lighting
This question is directed at Bob Fenner (unless someone else would like to
answer)...when you spoke November 21, 2003 at the Sacramento MARS meeting
you included some information regarding macroalgae.  Maybe I misunderstood
you, but did you say that Caulerpa was the only macro that could be lit
24x7?
<Yes, did mention. As far as I know the Caulerpaceans are the only continuous photosynthetically active macroalgae>
I mentioned this to a friend of mine that has Ulva & Gracilaria lit
24x7 in a refugium.  I looked through the information in your new book and
it did mention that Caulerpa could be lit 24x7, but there wasn't anything
saying that the others couldn't be lit 24x7.  Can you please elaborate why
Ulva and  Gracilaria shouldn't be lit 24x7.
<I would separate the area where the algae are into two compartments and only illuminate either side 12 hours a day>
  I know you mentioned it
during your presentation, but I think our table was on the 3rd pitcher by
the time you did so.
<Hee hee! Most photosynthates require or at least do best with a "dark phase" period... and so would grant these other algae such... either by turning their light off some hours during the "day" of the main tank... OR dividing and lighting only part daily. Bob Fenner>
Thanks
Marc Daniels

Animal Filter - 12/22/03
Hey there Anthony!  
<howdy Eric>
I have a question regarding the use of an animal filter, which I recall you discussing in your book.  
<yes...>
I'm using a 55gal. AGA for a 'fuge which has a 6" sugar-fine sand bed and Chaetomorpha algae.  
<excellent start>
I had planned to install a second 'fuge as an animal filter with Anthelia and Xenia as the "living filters".  As luck would have it; no room for the second 'fuge so I wanted to get your take on utilizing both methodology in the same container?  
<its never a good idea. Mixing plants and animals in culture in any combination will not allow both to thrive optimally. In this case... soft corals and plants more than most any other critters on a reef are competitive and can be very noxious to each other>
As long as I provide a partition for physical separation, are these species (Xeniids and Chaetomorpha) low enough on the "noxious scale" to effectively work together without battling each other to the detriment of the system?  Happy Holidays.  Eric
<there is not scale of measure that I am aware of between animals. Just studies on relative toxicity and noxious exudations by individual. Regardless... the practice of mixing the two is generally a bad idea. IN this case, with the partition and considering the nice size of this fuge... I'd be willing to see you try it. Neither organism individually is known to be especially bad (they are generally regarded as weakly noxious). DO let us know how it works out. Best of luck, Anthony.>

Refugium builder required 12/16/03
Hello Bob and the ever growing email pioneers , I am looking for a company or individual that can build a sump/refugium that I designed . I live in the North East , RI/ Mass , Please let me know if you can help . Richard
<Cheers Richard. I believe we can help you here. Do seek the advice of your local (and excellent!) reef club, the Boston Reefers. They have a website and forum on Reef Central. I am certain they can advise you of your local options. They are also the host of next years national marine conference to be held in Boston in September. Outstanding... looking forward to it. Anthony>  

Re: Refugium builder required
Hello Bob and Anthony , I am also interested in patenting this refugium and
then marketing this item . Seeing this is my first attempt at this I have no
idea where to start . I did some research and found a plastics company that
is interested in providing material and they also have a company that could
mass produce . Knowing somewhat about Bob's history I have the felling he
has been through this before with other products. Hopefully he can be a
wealth of information . I will also need a place to sell these items and I
can not think of a better home than WWM .
<Me neither... do try making and running a "demo" unit... once you have most all the bugs out function-wise, have developed ideas on how to mass-produce (jigs, frame boxes...), make a few and set them up at local fish stores... see what the public thinks, hopefully will pay... and we'll be talking. I would contact the Chuas at All Seas re pumps for your units... re-sale possibilities... do NOT give anyone exclusives in space or time... Bob Fenner>
                     Looking forward to your response, Richard