Refugium Advice in FAQ's (Steven's input)
Hello Crew,
I would like your collective advise on implementing a refugium on a reef tank I am planning for the Spring. I saw some conflicting views in the FAQs (whew, 3 days of reading) on how to best implement this. I am purchasing a 400 gallon (96"x24"x40") tank that will use a 48 gallon Ecosystem mud sump and a thin sand bed in the main tank. I want to maximize the fauna as I plan to keep Anthias and other plankton consumers. I plan to go real slow as I am re-entering the hobby and have spent the past 2 years reading, including Bob's CMA and Anthony's BoCP. I noted each of their replies in the FAQs, but I want to re-ask some FAQ questions to get clarification for my specific implementation.
1. Given the mud sump, should sand be used in the refugium to maximize biodiversity?
<I would chose one method or the other. Far too many times in this hobby various ideas are modified from their original design and when things don't work out the hobbyist blames the idea, not their implementation of it. Plenums are the biggest example.>
2. Should the sand refugium be a DSB or Plenum based setup?
<I see no difference between the two when properly installed.>
3. Would a DSB or Plenum refugium create a nutrient sink given the Ecosystem filtration?
<Again, not if properly designed and installed.>
4. Anthony does not seem to favor Caulerpa in the mud sump due to it's (potential?) effect on the corals.
<And I agree for corals, but I saw no mention of them. For fish-only, it is fine, though I do like Chaetomorpha for its excellent zooplankton production.>
Which seagrasses or macro-algae would you recommend for the mud sump and refugium respectively?
<It depends on your purposes. For zooplankton, I like Chaetomorpha. For nutrient export, Caulerpa is awfully good. For picoplankton, Thalassia seagrass.>
5. Given Ecosystem's recommendation on a 24-hr lit sump, should the refugium be lit on the same cycle or use an RDP?
<For Caulerpa, 24/7, for other macroalgae or true vascular plants RDP.>
6. What size would you recommend for the refugium?
<The bigger the better>
7. Would up-sizing the sump from the Ecosystem recommended 48"-long sump to a 72"-long sump increase filtration capacity and allow for more stocking potential?
<Quite possibly>
Thanks, Rob
<You are welcome. -Steven Pro>

Refugium Advice in FAQs (Bob's input)
Hello Crew,
<Hello Rob>
I would like your collective advise on implementing a refugium on a reef tank I am planning for the Spring.  I saw
some conflicting views in the FAQs (whew, 3 days of reading) on how to best implement this.
<Okay. Will render my opinions.>
I am purchasing a 400g (96"x24"x40") tank that will use a 48g Ecosystem mud sump and a thin sand bed in the main tank.
<Mmm, anyway to talk you into a larger container? Discounting "transit volume", displacement by solids... you may end up with just ten-twenty gallons of water in this sump/refugium. I assume you are employing a separate sump for your mechanicals (filter gear, monitors...)>
I want to maximize the fauna as I plan to keep Anthias and other plankton consumers.  I plan to go real slow as I am re-
entering the hobby and have spent the past 2 years reading, including Bob's CMA and Anthony's BCP.  I noted each of their replies in the FAQs, but I want to re-ask some FAQ questions to get clarification for my specific implementation.
<Okay>
1. Given the mud sump, should sand be used in the refugium to maximize biodiversity.   
<Not necessarily... as stated if possible, practical, do add more volume to the refugium... and restrict flow to-through the refugium to 2-3 turns per hour>
2. Should the sand refugium be a DSB or Plenum based setup?
<If you are a fan of plenums, go ahead. I am not in most set-ups, including yours. IMO/E you'll be much better off with a DSB>
3. Would a DSB or Plenum refugium create a nutrient sink given the Ecosystem filtration?
<Not likely, no>
4. Anthony does not seem to favor Caulerpa in the mud sump due to it's (potential?) effect on the corals.  Which
seagrasses or macro-algae would you recommend for the mud sump and refugium respectively?
<Halimeda, Gracilaria...>
5. Given Ecosystem's recommendation on a 24-hr lit sump, should the refugium be lit on the same cycle or use an RDP?
<RDP>
6. What size would you recommend for the refugium?
<As large as possible>
7. Would up-sizing the sump from the Ecosystem recommended 48"-long sump to a 72"-long sump increase filtration capacity and allow for more stocking potential?
<Oh yes! Bob Fenner>
Thanks, Rob

- Refugium Plans -
Hey Gang! <Hey! JasonC here...> This is a picture of the refugium I'm building. There will be a 295 gph powerhead providing water from the main tank thru 3/4" pvc pipe 1 1/2' into refugium, then, gravity fed into the sump under the main tank. It's a simple design, but, I'm open to suggestion for improvements! <Looks good to me, but you might want to leave out that sponge filter.> Where do y'all recommend ordering some short seagrass (Thalassia) or Gracilaria, turf algae, or, Chaetomorpha from? I haven't found a LFS in Denver to get this stuff from. <I don't know of any off the top of my head. I would ask around on the forums to see where other aquarists are finding theirs.> I also sent a picture of some algae on some of the live rock pieces in the main tank, would this be good stuff for the refuge? <I'm not sure... I see perhaps three or four different types there, but even then I'm not exactly sure which type they are. Got Caulerpa? What are your lighting plans for the refugium?> Will crushed coral work in the refuge? <Sure.> An update on the Green Finger that had "Mash 4077" surgery; 6 hours after being cut, it's bushing out almost as large as before the operation took place (a little shorter though!)
Thanks again,
Scott
<Cheers, J -- >

Re: mini-refugium?
Greetings WWM Crew,
  Your site is absolutely fantastic, and I've become a big fan and an addict.
<Me too>
As I grow in my aquarist experience, I've learned that I've just about broken every cardinal rule there is, and am hoping to correct my mistakes.
<Unfortunately that is the way it works sometimes, as long as we learn from our mistakes and try not to make them again.>
OK aside from that, which I'll be certain to ask for help about later on, here is my situation. I am running a 54 gallon corner bow front reef tank with 80 lbs. LS, 60 Lbs LR, corals and fish, etc. - its actually overstocked (based on parameters I've learned here) but I will take measures to rectify that soon.
<good plan.>
I have a wet/dry filter connected to the internal overflow system ( its under the tank in the stand ) and have a few powerheads in the tank for current ( for the corals ) a protein skimmer - which came with my wet/dry filter in the sump/filter and a UV set up in the sump as well. My fish and corals seem to be doing OK ( after multiple losses the first month ) but I've only been at this for 3 months total. My readings  are ph - 8.2, ammonia - 0, nitrite - 0, SG - 1.021 (29ppm), nitrate - 40, <Dang> and temp - 80 degrees. As you can see I have a rather high nitrate problem, possibly caused by the tank being overstocked, and the nitrate factory in my wet/dry bio media area, which I read a lot of people here are removing.
<could be part of the problem>
I'm not so sure that removing the Wet/dry media would have been a good idea, so I purchased a nitrate sponge ( funny little rocks in a sock like casing that I've connected to one of my internal 802 powerheads ) but the Nitrates have still not dropped after a week or so.
<From what I have heard, these are not that great.  I would not remove the bio balls just yet because you mentioned that your tank is overstocked, once you get that situation rectified it may be worth considering.>
My next plan was to take a 5 gallon quarantine tank that I've had up and running and trying to use it as a mini-refugium underneath the tank sitting next to my wet/dry. Since I do not plan on adding any more fish, and I've learned that the 5 gallon is probably too small for a Q-tank, I thought I might try this idea with the hopes of setting up some more LS or mud, and macroalgae and letting a 24x7 light run. My plan is to place a 2 small pumps inside the refugium and have water coming in and pushing out into the sump. My questions were
1: would this make any difference at all at only 5 gallons?
<Not much of a difference>
2: is this perhaps even detrimental
<If I understand the pump setup correctly (pump water in, pump water out) it could become dangerous, you may end up with wet floors, electrical fires, etc>
3: what other ways might I try to reduce my nitrate readings?
<Weekly water changes, maybe a 10gal refugium with a DSB, thawing frozen food and removing all food juice.>
Thanks in advance your site is a great pleasure to have access to.
Rao
<Best Regards, Gage>

Re: Refugium (#2 - or is that 5?)
Good Morning!
I've attached a quick sketch of the refugium - I'm not an artist, so don't laugh, k? The water line is actually just below the spout of the skimmer, which pours into the middle section of the refugium. 
<hmm...yes, but the water is shared and not totally concentrated/isolated in the first chamber. It is here that I suggest you add a small piece of glass or acrylic to dam the water slightly higher before it overflows into chamber number two. Also, the third chamber water level should be slightly lower than then second... if the dotted line is your water level... then you have too much water in the sump. Your actual sump is simply the third chamber: that is the sump portion (the lowest/last chamber). My concern is that the volume of this sump/3rd chamber is too small for the system. Can it hold all the water from upstream in the event of a power outage? I assume you have had a chance to test this but do be sure if you haven't.>
The water flow is so fast, I'm not sure whether the sand will ever have a chance to settle! 
<yes... one of the many reasons why I personally prefer an upstream refugium and not one that is below tank or sump-integrated>
Of course, I'll have to wait a few days and see. Anyway, please see if you can make sense of the drawing, and note that the baffles are equal height. 
<noted>
Some water is going to the skimmer, as it sits in about 8-9 inches of water (the skimmer is on a "shelf" of acrylic to raise it out of the water some), but most is pouring over the baffle, into the
refugium. 
<yes... largely bypassing the skimmer>
A lot of the water is just skimming over the top of all three
compartments, and going back to the tank.
<agreed>
Is a ref. supposed to have this much flow? 
<it can... slow flow refugiums are overrated. Still the 'pods need something to culture in... spaghetti algae, polyester pads, etc>
I think my copepods are mashed to mush by now! (Yuck, soggy cereal!)
<still edible to coral and fishes <G>>
-Cathy <><
<We may need to chat by phone on this one. Best regards, Anthony>

Re: Refugium (#6, I think)
Hello again!
Ok, the third compartment, with the return pump, DOES have a lower water
level than the other two. (It didn't last night, but the water flow is
settling.) 
<evaporating...raising your salinity slightly in the process. Do be conscious of this. Target a desired running level and keep it constant with daily additions of top off water if necessary... you know the drill :)>
Just enough to cover the pump and the sponge filter on the end of
it. We haven't tested it for if / when we lose electricity, 
<Yikes!>
as this project
was finished late last night. 
<Ha! braver than I am... you build it... THEN went to sleep... testing it next day. Some concern about the sequence of events here... heehee>
Will do that today, along with the other tweaks needed.
I added a plastic lid along the wall of the first compartment (the spout
hangs over the wall, so couldn't be full-length) and that seems to slow down the rate of water going over the baffle. (The lid is on it's side, not as a covering, but an extra height to the wall.) 
<yes... a dam, per se>
Still doesn't ALL go through the skimmer, but keeps the water movement in the 2nd part going.
<not sure here... I don't think so. The raw water dumps into the first chamber... not plumbed into the skimmer right? If so, some inevitably bypasses. We are just trying to minimize that>
The skimmer has foam, but not much. Air tube is fully open, and I can't tell where the water level is in the skimmer. Why did they have to make it gray? Hee Hee. Have ordered a mixed batch of "red" and "brown" algae from Bill's Reef, hope to get some plant life going. Oh, and "Sea Grass" is included in the order.
<awesome... be sure to know that seagrass must be planted at least 3" deep. Deeper is better. That means a sand bed of around 5-6" minimum>
Great states alive, how come you guys are on the East and West coasts, but no one in the middle of the U.S.? Y'all need to come back! LOL We'll feed ya more brandy ;-)
<yummy! and with thanks! It was shared at the banquet with all friends... Bob Fenner, Leng Sy (Aquatic Ecosystems, etc)>
THANK YOU THANK YOU THANK YOU -Cathy <><
<our great pleasure, Anthony>

Sump/Refugium
Dear WWM Crew,
I have a refugium question. My set up includes the following:
1. 180 gallon acrylic tank (78"x26"x24") with two internal overflow boxes (each with 1 1/2" bulkheads) that drain to sump #1
2. Sump #1: acrylic 22" L x 22" W x 16" H (for CS8-4 Euro Reef skimmer) with two 1 1/2" bulkheads that connect to sump #2 acrylic (48" L x 24" W x 16" H). Sump #1 is behind a wall. Sump #2 is under tank. I also plan to maintain a 10" water level.
3. Two Mag-Drive 12 pumps for return to display tank. Return plumbing is built into the overflow boxes and exit at the top of the tank.
Now for my question. My thoughts have been to build a refugium in the
center of sump #2. Inlets for sump #2 being near one end and the return
pumps at the other end. Any thoughts as to partitioning for the refugium,
<I would retrofit this to look similar to an Ecosystem-style sump/filter, but sans bioballs.>
substrate depth/type and lighting.
<This really depends on what you want the refugium to do; nutrient export, pH stability, plankton production, etc. It also matters a good deal what the 180 is intended to house; big messy eating predators, plankton feeders (like Anthias), a SPS, clams, LPS, soft corals, etc. Please see the information available on www.WetWebMedia.com regarding refugiums.>
Any other comments concerning this configuration would also be appreciated.
<As there is no one perfect lighting for any tank, there is also no perfect refugium. Everything needs to be tailored to you and your tank's needs.>
Thanks for your website. Brian S.
<Have a nice day! -Steven Pro>

Sumps, refugiums, mud filtration, oh my!
Hello again,
Thanks for all the wonderful info that you provide. It helps to bring order to what sometimes seems a  very difficult hobby. Here goes......
I have a 215 gallon mixed fish and invert and I am in the process of setting up a refugium. I currently am using the Berlin method (350 lbs of live rock with lots of skimming). What is an ideal size refugium for me?
<Generally, the bigger the better. Anything under 20 gallons is not worth doing.>
Should the water in the refugium go all the way to the top?
<Like a standard aquarium, overflow and plumbing considerations need to be factored in of course.>
How large of a space should the plenum be?
<I am going to refer you to the published works of Dr. Jean Jaubert.>
It is my understanding that the plenum is simply an empty space underneath the substrate.
<Correct>
What are the physiological effects of the plenum/why is it necessary? Should the substrate be layered with different grain sizes (why) and separated by additional eggcrate? How should the layering be done?
<Again, with the above questions, go to the source of this methodology. Almost all problems with plenum systems have to do with improper installation.>
Is a mud type substrate recommended or a larger grain or some combination?
<A mud substrate is a completely different methodology by Leng Sy of Ecosystem Aquariums.>
What should the grain size be? Where can I find step by step plans/blueprints for the construction?
<You should be able to find out all your questions using a simple search engine on the internet.>
Should it be lit 24/7 or alternated with the main display tank lighting?
<This depends on which methodology you employ.>
Does the refugium need to be compartmentalized?
<This helps with controlling flow and surface skimming.>
Will the pump kill all the critters before they get to the main tank since the refugium will empty into my sump first?
<No, not all.>
What is a good seeding package to start with?
<Livesand and detritivore kits from several sources to increase diversity.>
What are the essential macro-algae plants that should be in the refugium?
<Again, this depends on your intentions, nutrient export, larger plankton production, nanoplankton, etc.>
My space will allow for a refugium that is 48" x 9" x 20".
<About 35 gallons.>
Will this size be enough to do the job?
<You should be some added benefits.>
Also, I have heard all the pros and cons of UV's and have decided to use one. It has been running now for 6 months. My display tank has four drains and I plan on using one of the drains for the refugium. The other three returns will drain into the sump where I have a Euro-Reef skimmer and my mechanical filtration. The pump return is Teed off and 1 return flows to chiller and the other though the UV. Both returns go directly into display tank after that. If I have the refugium return directly into the display tank, can I continue to run my UV?
<You can but it will negatively effect plankton production.>
Any input would be much appreciated.
<Please search both our site and the internet at large for refugium ideas.>
Thanks, Steve
<You are welcome. -Steven Pro>

Nitrate Removal
Hi Bob,
To continue (Sorry), I have a couple of little technical problems re: refugium. Currently I have a shelf (fitted recently for now removed trickle filter) which I would like to support the refugium on, I would like to include the following in the sump in sections (if sections are needed) overflowing to the next section.
Feed into 1.
1.Protein skimmer (in/out from same section)
2.live sand 6in(depth ok?)
<If layered (two, the larger below), three inches would be my maximum (the upper, more fine of about an inch, the lower more coarse two at most>
3.Live rock full to top with 24/7 light.
4.Heater.
Is there a particular order I should put these is? i.e.. 1 => 2 => 3 => 4 => main tank? would the heater be fine in either section?
<The heater is best in the main tank really... as things do go haywire at times... good to have it heating the water there rather than the sump or worse, air... The live component should be first, the skimmer in a compartment/arrangement where the water level is steady (in most scenarios with an area where the water is backed-up to a given height, overflowing to the next. The LR can be placed on top of the LS area>>
The technical problem because the refugium will be above the tank it will have gravity flow back into the main tank, but getting the water from the main tank to the refugium, I tried to use the pump with my cyclone to move the water up to the Skimmer and them into the tank but the skimmer became
inoperable (not enough water pressure), the same ensued when I put a second pump in series with the first to get the water to the skimmer, should I just try and get the water to a sump above for the skimmer, with an overflow into the other sections (would this be more efficient?),
<Yes... leave the skimmer with its own pump>
also with the flow from the skimmer will this be too fast for the LR/LS if so do you have any
suggestions for a bypass.
<Yes. A tee and a valve to divert just some of the water to the above unit sump, bypassing the rest for circulation only.>
There is also the problem of weight/size limit for the shelf approx 30-50Kg and 6in wide by 3feet height 2feet, will this be enough space for a refugium? (Afraid no space below or beside tank is in
office at home next to 3 computers and you'll like this bit, its above 2 servers).
<Yikes... am NOT a fan of seawater around computer gear... some quick calculations will reveal that seawater at about 8.2 pounds per gallon, and three cubic feet or so possible, approx. 7.5 gallons per cubic foot... that you cannot have even all water in such a size container, let alone more dense rock and sand... the unit should still function with about half the height employed...>
Thank you for your earlier emails, I have now a less foggy direction to proceed tentatively.
Alex (Sandgate, UK)
<Be chatting, Bob Fenner>

Re: Sump/Filter Design
Hey Guys,
<Cheers, again>
What if I used a skimmer, but used the sump design I proposed below. I know the flow would be too high to fully benefit from the Caulerpa nutrient uptake, but it would remove some, it would give me another deep sand bed, more live rock, refugium for critters, and extra oxygen in the water at night leading to a more balanced pH because I would light it 24Hr. What do you think? Thanks in advance for the help.
< I can tell you that in either design, if the skimmer has to suffer from a fluctuating water level it will perform poorly. Since you are thinking about putting the skimmer in the 'fuge that will then overflow into the sump... I say it is a better idea (static water level in 'fuge)> Mike
<best regards, Anthony>

Re: Sump/Filter Design
Hey Guys,
Let me clarify. I want to make a refugium/sump. It would only be one unit. There would be 3 compartments that are all connected. The first compartment is where the water from the main tank overflow goes, there would be no fluctuation in water level. This is where the pump for the skimmer would be. In order for the water to get to the next level it has to spill over a divider. The next compartment is where the refugium would be, that would then overflow into another compartment that would return the water to the main tank.
<I understand your intended design now and it sounds good.>
Water levels would always be constant in all compartments just like a regular sump.
<That is not really correct. I do not know if you know this or not, but the water level will fluctuate in the last compartment (where the return pump is located). This is where you will see all changes from evaporation. You can minimize this by dripping in top-off water, use of a dosing pump, or one of the polar water type top-off designs, but there will still be some minor changes. The other two compartments will remain constant, though, and it is still a good plan.>
Thanks in advance for the help, Mike
<You are welcome. -Steven Pro>

Going Reef-ish II - Refugium Confusion
Steven,
Sorry, I forgot the model. Thought I included. It is an Amiracle. I
inherited it and it doesn't have a model number (that I can see...I
should look where?? ).
It is about 22 inches long and maybe 12 to 14 inches high and about 11
inches deep -- most definitely rectangular in shape. It is SUPPOSED to be a year old (I got all this stuff used from a LFS that has gone out of business and didn't know what questions to ask at the time I bought it). The bio ball chamber is more like 2/3 of the space of the entire unit, the "pump area" is like 1/3. I don't have one of the models that has that "transitional area" between the bio chamber and the pump chamber that you see in lots of the books (Tullock's for example) where you can put a foam sponge or whatever.
In my unit, the two chambers share a common wall that runs from the top of the unit to about an inch (maybe an inch and a half) from the bottom of the entire unit. This area is about 4 inches long. Since the sump/pump area is kind of small, my pump takes up almost the whole area (and I'm not sure what model it is, either).
Does that give you any more idea? I can get pump and wet/dry models
tonight when I go home if that would make things easier. I am not
technologically advanced enough to have a 'puter at home AND at work (I live on one between 8a and 6 or 7p) or to have a digital camera
(although that IS on my list of acquisitions to make).
Thanks! and let me know if I need to go investigating for models
tonight.
<The following is from a second message with more details (inserted and answered here for convenience sake).>
Duh... when in doubt, go to the manufacturer's web site. (you'd never
guess that I work with tekkie geeks for a living, would you???) I THINK I have the SL-150 (maybe the 250). Mine looks almost exactly like the picture on the right. Mine has 2 intake areas on the lid though (like the picture of the Maxi Reef filter on the right) http://www.amiracle.com/filters.htm#advancedspecs
<Third email inserted also.>
OK. Measured last night. Dimensions are 24X 8x14. So I DO have the SL-150. The pump/sump area is 8x8.
<Ok, now that we have the all the facts I shall try to give you a solution. The easiest thing I can think of is to drill a large hole, or several holes depending on the flow, similar in size to a bulkhead fitting, near the top of the dividing wall of the Bioball chamber. And then to seal a piece of acrylic or glass into the bottom forcing the Bioball chamber to fill to the new hole(s) level. That way you can make this full section your refugium with sand and liverock and have little to no worries about sand getting into your pump. The other thing to strongly consider is if you would be better off buying another tank or Rubbermaid-type tub of similar size and building that exactly into the refugium design you want and try selling the wet/dry. -Steven Pro>
Rebecca

Re: Going Reef-ish II -- refugium confusion
Steven,
Thanks SO much and sorry for the multiple mails.
<No need to be sorry. I kind of needed all the info.>
2 follow up questions if I may....
<Fire away>
1) what kind of bit do you use to drill through acrylic (I have a pretty fun Black and Decker drill and I bought the "bit kit") without breaking it?
<A VERY sharp hole saw bit. Can be picked up a any Home Depot or the like.>
2) if I bought just a 10 g aquarium, wouldn't I have the same problem?
<No, much easier to deal with. Can you fit anything larger than a 10 gallon tank into your stand?>
How do I divide the pump area from the "grow/filter" area?
<Using a simple glass divider where instead of having to drill holes, you just leave the divider an inch or two from the top and allow the water to overflow into the pump section.>
I could silicone a divider (piece of plastic is OK, right?) though into an aquarium, couldn't I?
<Yes, but I prefer glass so that it will not bow. You can get glass cut to size at Home Depot, too.>
Or use an "aquarium divider". Would that work?
<The small holes that come in these would not work right.>
Then I could use the wet/dry for my next aquarium (these things are like bunnies or junk food -- you can't stop at one!
<Yes, very addictive. At one time, I had as many as 7 tanks of various sizes. Now down to 4.>
Thanks so much for all the help. You guys save us all tons of grief and make us LOTS smarter!
<Thank you very much. -Steven Pro>

Going Reef-ish III -- refugium confusion
Gentlemen (and you are ALL gentlemen...)
<Why thank you kindly.>
Last step left in my reef-ish conversion is converting the wet/dry to a
refugium. I'm actually in process with this.
I have:
1)Pulled about 1/2 the bio balls over a several day period and put LR in
with the remaining bioballs (monitoring parameters as I go).
2) Mail ordered several lovely different kinds of macro algae from IPSF
(they arrive tomorrow and I can't wait).
3) read the article on WWM, in CMA, section in Anthony's book and the
FAQS (all 3 sections) on refugiums.
<Fantastic!>
Still have one TINY area of not-sure-what-to-do to make this work. .
I have a 15 lb bag of reef sand (know I won't need the whole thing) that
I will put in when I'm done the bio-ball/rock swap and will "plant" the
algae in with the rock/sand. Here is where the confusion comes in.
I am not sure what to do about the small space between the bio ball
chamber and the section that holds my pump. Water has to go from the
bio chamber to the pump chamber, so I can't silicon a piece of plastic
over the area (saw that though...). But I don't want all my sand in
there, either (in the pump chamber). Get a little piece of fine mesh
plastic screen? The area is about an inch high and maybe 4 inches long
and runs along the bottom from front to close to the back of the bio
ball chamber.
<A picture would be helpful or a brand/model for your wet/dry so that we could reference that. Most brands of W/D's have half the volume dedicated to bioballs and the other half for the sump/pump. Can you silicone in a piece of glass or acrylic that would divide the sump portion in half, but only go like 6" high. So that you maintain at least 6" of water in the Bioball area and in half of the sump area. If you send a picture or drawing, perhaps we could be of more assistance.>
A final suggestion in this area (shoot me to a link if I missed
something -- I have no problems reading info I missed!) would be greatly
appreciated.
I have so much more knowledge starting over now than when I initially
began my marine journey.
<Glad to hear it.>
Thanks as always. Rebecca
<You are welcome. -Steven Pro>

Filter/Sump/Refugium
Good afternoon Bob or Team Fenner...
<"Team Fenner"... now that is a cool label. I'm going to talk to Bob about getting Jackets with "Team Fenner" embroidered on them... No, better yet: sequin Speedos. Ughh... I think I just made myself sick <G>>
I have a few questions for you regarding filters. Currently I have a 90
Gallon Reef tank, many soft corals, a few hard corals, various fish and
inverts. I'm currently using a Trickle Filter in my tank stand where the
water first flows through floss material and then drips over tons of
bioballs. The water parameters are good except the Nitrates are extremely high 90ppm due to what I think is the trickle filter. 
<no question about it>
Since I'm an engineer and enjoy projects, I was going to attempt to manufacture an acrylic sump with a built in refugium. I've put together a sketch (included) of my 2 designs but I have a few questions that are probably easily answered.
1) I was initially going to go with a three chambered sump. The first stage being a trickle filter. 
<with enough live rock, the bio-media is not necessary and is actually an impediment>
Then I saw some designs that utilize submerged
bioballs. 
<a staggeringly horrible idea that reduces efficiency of bio-media for many reasons not the least of which is dependence on submerged water for O2 ( a limiting factor to their growth/life)>
That wouldn't be considered a trickle filter then because their is
no air exchange to harbor the bacteria. Wouldn't submerged bioballs merely be a nitrate factory due to the build-up of larger detritus gunk in the bioballs? Wouldn't this be a high maintenance filter? I don't want that.
<yes... horrible in so many ways>
Would putting a trickle filter as an extra means of filtering the water add to water quality or would it counteract the refugium?
<works against good live rock, refugiums, aggressive skimming, etc>
2) Should I not even have bioballs or any mechanical filter means as a
prefilter? 
<Bingo>
Should I instead tee of the water draining from the tank and let
most into the sump and let another elbowed connection control the water
input into the refugium thus slowing the current? No trickle filter? 
<agreed... at best, just a settling chamber for large particulates>
No Filter sponges?
<only if maintained weekly or better... a pain in the but, but polished water nicely and serves as a ready filter media for a quick QT tank when needed>
3) I thought refugiums should have a low water current 40-100gph. 
<nope... depends on what you are culturing in the refugium. Low to scary high may be needed. Very brisk surge/flow needed for seagrasses>
I have a pump that is rated for 1200gph at 3' head. I would need another compartment to decrease the flow rate, correct?
<could just tee a bleeder line in a loop back into the low reservoir of the sump>
Any information would be much appreciated. Thank you in advance for your
time.
<best regards, my friend. Anthony Calfo>

Refugium
Dear Sir;
I would like to set up my 75gal tank again and this time I would like to filter with a refugium. Can you recommend a good book to purchase on the subject?
<Yes, the best: Anthony Calfo's Book of Coral Propagation. My review of this friends tome here: http://www.wetwebmedia.com/bkcoralprop.htm
Available from the author, Amazon, stores in the interest, etailers listed on the site. Bob Fenner>
Thanks Dr. Fletcher

Re: Refugium
Thank You. Have ordered Anthony Calfo's Propagation book.
<You will not be disappointed. The education and inspiration there are worth many times the purchase price, time investment to read. Bob Fenner>

Refugium
Bob
I have read the many articles posted about refugiums. I am getting ready to set up a 125 gallon reef tank. Is there a good book on this topic only?
<Not as far as I'm aware. There is some coverage in The Modern Coral Reef Aquarium v.1, John Tullock's Natural Reef Aquariums... but likely the best coverage is in Anthony Calf's Coral Propagation book. My review here: http://www.wetwebmedia.com/bkcoralprop.htm 
Or just "writing your own", by reading through the Refugium, Sump areas on WetWebMedia.com's Marine website... with added input from BB's like Reefs.org, Reefcentral, our chatforum: http://wetwebfotos.com/talk/ and others... and looking through commercial websites like Leng Sy's Ecosystem Aquarium...
Bob Fenner>

Many questions
Great site, I have already read through a lot of the material here (just ask my wife, I think she has had about enough).
<You think your wife gives you grief for reading, imagine what my wife says for all the time I spend answering the queries.>
Anyway, thanks for all the help. I have 10 years of experience with the old style, saltwater, fish only tanks, wet dries, lots of carbon, UV, magnum 350, skimmer, 1/2" of substrate, you know what I am talking about, the old way.
<Gotcha>
However, I am a newbie when it comes to deep sand bed systems. I have been out of business for the last two years because of "work" (nasty word). When I quit, I had three tanks which I sold, but kept all the rest of my gear. Wow, am I glad I did, it still cost me a small fortune. Anyway, I have a 75 All-glass about seven weeks old with built in overflow, about 70 lbs. live rock, 29 gallon sump/refugium (very similar to a EcoSystem, Jaubert plenum (wish I had put this in my refugium), Rio 2500 return from the sump, one 802 and one Rio 1700 for current inside the tank, AMiracle 4, I think ps, protein skimmer (Its about 15 years old has two chambers and uses air stones, but works great), 4x96 watt PC (10k, 67k, 03, 71k) with a fan blowing down onto the water. Two Ebo-Jager 100 watt heaters, water temp is slightly under 78 F. Any suggestions on improvements to this point?
<Seems reasonable>
Water quality is; pH 8.6, ammonia, nitrite, and nitrate zero. I am about to order additional test kits but do not have them yet. I have 9 hermits, 18 snails, one blue damsel (all added after the tank had cycled), one serpent star fish that is alive but I hardly ever see (very concerned, he was a gift),
<Very normal to not see these starfish.>
lots of stuff from the live rock and Caulerpa in my refugium that is growing very well. I use two 13 watt PC, 24/7 for the refugium. When would you start adding corals?
<It seems like you are ready.>
Could I add three or four small to medium corals at a time or is that to much?
<No, should be fine.>
I plan on starting with soft corals and mushrooms and move into the harder stuff as I gain experience. I do hope to get into clams way down the road.
<You tank does not seem to have enough light for clams.>
I also would like two or three percula clowns, not sure if the blue devil will be a problem, my luck he will be, a tank tear-down already. What critters should I add to my refugium?
<I would leave it alone for now and allow the smaller hitchhikers to flourish.>
Should I add scarlet hermits, snails?
<If anything, perhaps a few snails.>
I have a lot of detritus accumulating just over the baffle. Had a little bit of red slime develop there that changed to green slime but is going away now. In the main tank I get a little green algae on the glass each day but I am running lots of light for 12 hours, I kick the actinic on/off a couple of hours before the daylights. Do you see any problems with any of this?
<Nothing stands out>
I have a good growth of what looks like reddish purple hair algae that has been cropped, or maybe the purple tang food I used to buy. I also have a lot of bright blood red algae growing on my live rock. I suppose this is good?
<Do look over the algae sections of www.WetWebMedia.com to identify what you have growing and whether it is considered a nuisance or not.>
Sorry this is so long. I would like to add a refugium next to my main tank. Should I leave the Caulerpa growing in the sump/refugium and have two refugiums or just make the one a deep sand bed sump?
<This is up to you. I am planning/building a new tank for myself and my current plan is to have one Miracle Mud/Caulerpa refugium under the tank on a 24/7 light cycle and a second Thalassia sea grass refugium above the tank on a normal light cycle.>
I am using aragonite sand about 2 ½" deep, should I add "expensive" miracle mud to either of these?
<I would choose one medium or the other and not try to mix them in the same refugium. I am planning on one Miracle Mud unit and one aragonite DSB.>
Many more questions, hope this makes sense. I guess I better quit for now, let someone else get through. Looking forward to your answers and thanks for all you do..
<You are welcome. -Steven Pro>

Refugium (Design)
mornin'
<Good morrow>
I am in the 'thought' stages of designing a refugium for my 75G reef. I don't want to use a standard tank and will make one from glass or acrylic. (both available locally). Planning on basic fuge' construction
using the ideas I have gotten here. (thanks!)
<Welcome>
Is there any proportion (long/short, deep/narrow, tall/short) that gives the 'fuge an advantage? 
<Larger, flatter>
What about turnover flow? I have seen anywhere from 5-20x per hour.
<Slower is better>
I am thinking 48"x10"x10". This would give me a volume of about 20G US
and I figure about 14-16 after DSB and rock.
<If you have the space... make this sump taller... to allow for transit volume (should the pump/s, electricity fail), more flexibility down the line (DSBs and such)... Bob Fenner>
Thanks, Don

Sump / refugium question
I currently have made the mistake
<Ominous>
and started to ponder on the creation of a
sump / refugium for my 135 SW tank. Attached is a basic diagram for what I
am thinking of. Basically, the water comes in from the tank via the
overflow, and enters the sump. the water travels down, under a baffle (A)
and then back up to the top of baffle "B". It then enters the refugium area
which will contain LR, Macro Algae, and a DSB. Water then overflows into
the pump chamber and back into the main tank.
<Okay>
Here are my thoughts at this time. In looking at the diagram, there is a
possibility of dead or anaerobic spots along the sand bed due to most of the
water moving along the top, while not along the bottom near the sand itself.
To possibly solve this problem, would it be prudent to create holes along
baffle "B" for water to pass through? 
or would the wall between the
refugium and the Pump chamber also create a dead spot?
<I wouldn't be concerned about either... sufficient water movement here>
Another idea that was suggested by my LFS was to elevate the DSB off the
bottom with screens and egg crate, remove baffle "B" and have the water
forced up through the DSB, into the refugium, and then over the wall into
the pump chamber.
<I wouldn't do this... too much water flow to make the DSB worthwhile for any real purpose.>
I have heard of some systems that do this, but with Miracle Mud. 
<Really? Leng Sy didn't intend this...>
(any
comments on that, I have read some threads that basically call it an
equivalent to back yard dirt, nothing to say that it IS ocean mud - anyhow,
too pricey for my pocket book)
<"The proof is in the pudding"... in other words, if it works, isn't all that expensive in view of what it does, results it produces, livestock costs it protects...>
Lastly, I plan on having my Berlin turbo skimmer in this as well, but due to
the massive size of its submersible pump, I was considering placing the pump
in the first chamber (at the bottom of the intake) plumbing it across the
bottom and placing the skimmer itself in the same chamber as the return
pump. The output of the skimmer would drain into the refugium. All the
plumbing would be sealed so no water would leak into the pump chamber
without going through the refugium first (unless pumped into the skimmer)
My thoughts on that were basically, pumping the skimmer before the refugium
would prevent skimming any critters that decided to go on a waterfall ride
from the refugium.
<Sounds reasonable. You might "glue", adhere the second baffle wall in in such a way that it can be "pulled up" (as in a race/guide along the sides, bottom) so that if you want to experiment with the suggested "reverse flow" arrangement of water under the DSB you can more easily try it out... This flexibility will also allow you easier means to try a shorter/taller second baffle wall, one with holes in it...>
I was looking at building this in a 20-30 gal tank.
Also, would a setup like this suffice as a primary filter for what will
become a reef tank?
<Yes>
Currently the tank has roughly 3-4 inch sand bed of varying degrees of sand
from sugar sized to small shells. It also currently has about 50 or so
pounds of LR with the intention of adding about 100 more pounds when money
allows.
<Okay>
Thanks again for all the information you have previously provided.
Andy
PS in to respond regarding my previous question about my Tidepool SOS
overflow, I knocked out every other "tooth" and moved the filter pad up to
cover the open holes. Now it looks as if none of my fish can enter the
overflow, and it dramatically increased the overflow capacity. In-so by
doing that, it no longer traps air in the siphon. So far so good from what
I can see.
<Ah, a good fix. Bob Fenner>

Idea
I had an idea after reading one of the posts on your message board
and I did not know where to go with it. The post was concerning the CPR
hang-on refugiums. I looked it up in one of my catalogs to see how big
it was and noticed how expensive and small they are. I then thought
about it and had an idea to use a Hagen Aquaclear 500 as a refugium. 
<The "other shoe" is about to drop on these approaches... know of a couple of folks/companies looking into hang on, injection-formed containers... thank goodness... the price of such is about to plummet>
I have done something like this before, but without lighting it. I just
filled the basket with liverock rubble and it worked rather nicely.
<Yes... Pete and I experimented with these (with/out skimmers, CO2 injection, different types of biomineral/alkalinity reactors, macro-algae, substrates (natural and not) for the last years... You've never visited here as I recall.>
The
current idea is to retrofit the lid into some sort of hood/light. They
should sell well under the CPR units of comparable size. What do I do
with the idea? 
<Sold! Do check with the Chuas at All Seas for fab small CF lighting fixtures at very reasonable pricing here...>
I could try to build one myself and write something up
for one of the trade magazines (probably FAMA as they are the only one I
have noticed will use brand names in their articles). Or should I
approach Hagen directly?
<We should talk... and you might want to chat all this up with Leng Sy (Ecosystem)... your idea has been "kicked around" for quite a while... and you will need something proprietary, semi-spectacular to at least notable to get beyond marketing...>
I am not looking to become a manufacturer or
become rich off of this one idea, but I do not want to see these in
stores and get nothing either.
<I will send this note to Peter.C (biz associate, partner in fun) for his input. His thought was to have the bodies of his/our units OEM'ed in Mexico, over the border... but have talked with Jason.K (Aqua-C) re jigs, fashioning at least the first few hundred, thousand units in the U.S. to make sure they're a go-er... As stated above, there are folks who want to have something like the Tetra-Tec HO unit body injection molded overseas... you should get hot on this if you intend to do anything... Bob Fenner>
Thank You,
Steven Pro

Steve Pro's idea
I don't know who this Steve Pro is either, and btw, I've never
posted here either. I think you are doing a wonderful job anyway.
<... okay>
Back to his idea. And he is sure a lot more knowledgeable than I
on just about everything aquarium, but I do have some thoughts
on this, being pointed. :-)
<Fine... Steve is a person who has worked in the retail end of the trade and self-employed with an aquarium service company...>
>it was and noticed how expensive and small they are. I then thought
>about it and had an idea to use a Hagen Aquaclear 500 as a refugium. 
The thing I would wonder about would be the flow rate. If it could be
adjusted
to be quite slow. I don't know as, although I have a Whisper on my QT,
I've
never played with the flow rate. You gotta have a slow rate.
<Yes>
><looking into hang on, injection-formed containers... thank goodness...
>the price of such is >about to plummet>
>have done something like this before, but without lighting it. I just
>filled the basket with liverock rubble and it worked rather nicely.
><Yes... Pete and I experimented with these
Oh sounds like a neat idea. For my next tank....
><We should talk... and you might want to chat all this up with Leng Sy
> (Ecosystem)... your id
Uh, how to say this, but Leng Sy is not known for competitive pricing.
And I am saying this as a proponent and "user" of his system.
<Yes... but to grant you some insight (Leng and I are friends) he makes very little money on his units... the costs of the containers themselves is quite high>
><something like the Tetra-Tec HO unit body injection molded overseas...
><you should get hot on >this if you intend to do anything... Bob Fenner>
I think the clear look would be nicer than Tetra Tec's black box.
Not that you were actually talking about look though.
<Agreed... but it does hang on the back, get coated with gunk in most peoples settings>
>Steven Pro
Your friend,
-des/Jane
<Bob Fenner>

Re: Steve Pro's idea
>Uh, how to say this, but Leng Sy is not known for competitive pricing.
>And I am saying this as a proponent and "user" of his system.
><Yes... but to grant you some insight (Leng and I are friends) he makes very
>little money on his units... the costs of the containers themselves is quite
>high>
To comment on this, the Ecosystem40 box is extremely well made--
not P.O.S.
<Yes... made for Leng by real craftspeople... just expensive>
Very nice looking, solid, and nice components (maybe
except for the darned Rio, which is small), for example very nice
Jalli light fixture. Hardly even a scratch on mine-- except for lovely
developing salt creep. :-) And I'm not complaining too badly, works
good.
<Let's settle on works well, okay? Bob F>
--des

Refugium set-up
Hi Bob, Welcome back, I'm glad someone posted bail for you. Anthony and
Steve did a fine job while you were out. 
<As always. They are competent, honest... articulate, and have a sense of humor to boot!>
I have a 150 gal tank has been
empty for three years due to some remodeling. It seems much has changed in
the industry.
<Yes>
After reading, and re-reading your entire site, I've decided
to make some changes to my set-up and would like your advice. Please find
the attached diagrams.
<Have downloaded and perused them>
The existing equipment will remain with a few minor
changes: The bioballs will be replaced with batting and a few pieces of live
rock in the sump. The return from the Little Giant MD4 will run behind the
tank instead of through the drilled overflow and I will add a calcium
reactor.
<All good improvements>
I think I have enough room to squeeze in a 19x14x24H Refugium under
the tank. I want to use the existing drilled 1/2 in hole in the overflow to
gravity fill the new Refugium and return this water behind the tank as well.
The tank is currently cycling with 1 1/2 " of LS and 80lbs of LR and whatever
critters it came with. I plan to add 3 more inches of LS ASAP.
Here come the questions: How much batting should be placed in the wet/dry
portion, if any?
<Not much... a couple of thin (half inch or so layers... two so one can be replaced regularly... to keep gunk out of the pump>
Do I need the existing drip plate or just dump it on the
batting? 
<Just onto the batting likely... perhaps a floating box of Styrofoam can be fabricated to hold all in about the right place... with holes in bottom, shallow sides to allow overflow...>
What are you thought on the UV/Skimmer inline (the skimmer seems to
be working very well)?
<A fine plan>
Are you sure I don't need to use carbon with this
ozone set-up?
<Not necessary, or advisable... not enough ozone to worry about>
What size pump/flow rate would you recommend for the new
Refugium? 
<Small, slow flow rate... look into the Mag line, the low numbers>
Do I need the foam before the pump?
<Just something large like a pin-type wet-dry media plastic thingamajig in the intake>
And one more, for now,
lighting suggestions over the new Refugium?
Thank you O' wise one!
<A couple of watts per gallon or so... of CF is best... can be had at Home Depot... Bob Fenner>
Jim Schaefer

Algae bed/Mud + Refugium? + Skimmer?
Hi Dr. Fenner,
<Just Bob please>
I respect your experience and I appreciate your willingness to share it.
I have read through all of your FAQ's on refugia and mud filtration and I would
like to bounce a few ideas off you.
I am just getting started down the road towards acquiring my first saltwater
system. I've been reading for the past 6 weeks and have become a fixture at the
LFS's.
<A good place to study>
The goal of my system is to have a healthy system with the lowest possible
maintenance necessary.
In addition to the common reef inhabitants, I am MOST interested in keeping one
or two Mandarinfish and I am coming to understand the challenges they bring.
I have seen some algae/mud systems (no skimmer) in operation and I am very
impressed with the quality of the water they produce. I understand that the
water in these systems needs to be turned over about 5 or 6 times per hour. Is
it possible for this type of sump to act as a refugium and produce enough live
food for the Mandarins to eat with the water moving this fast?
<Yes>
Secondly, what is the survival rate for the plankton if it is being pumped at
this speed?
<Very high. I would speculate in the ninety plus percentage... those critters are tough>
So lets say that you believe the water is moving too fast to grow enough food
or the pump is killing too much of the plankton and I add a true refugium above
the tank to grow food and other species that aren't suited to the main tank.
I'll move the water through here pretty slowly and gravity feed it back to the
main tank.
<Fine>
Now I have crystal clear water and yummy food for the Mandarins.
Finally, the skimmer question comes up. I understand you like them and I will
probably end up with one. However, I will probably begin without one as an
experiment to see how much fish-life I can safely support without one. 
<Better to start off with one, then turn it down, cycle it on/off...>
The
research I have done and the feedback from others seems to indicate that an
algae bed/mud system without a skimmer is sufficient if you keep the fish
population fairly low. I'd like to do some tests on this theory and try to
better understand if/when the skimmer becomes necessary.
Finally, I'd like to hear your feedback on running the skimmer, the algae/mud
bed, and the refugium together. My thought would be to put the refugium above
the tank and the skimmer and algae/mud below in the sump with the skimmer
coming after the physical filtration and before the algae/mud bed.
<Okay>
What of Leng's argument that the skimmer will take the plankton and trace
nutrients out of the system?
<To some degree true... But what of the advantages of running the skimmer?>
Given that the algae/mud bed is lit 24hrs/day, I understand that the use of a
refugium that is only lit 12 hours per day on alternate cycle from the main
tank is optimal. Can you explain how/why this reduces the fluctuation in
chemistry?
<Mmm, optimal? Depending on the types of life employed, either lighting regimen can be "optimal" for the system, water overall. Alternating the cycle can save Redox, dissolved oxygen vacillations... leaving the light on continuously on the refugium/sump can accomplish the same>
In this scenario (algae/mud bed lit 24hrs/day - refugium lit 12 hours per day
opposite lighting of main tank) , what do you think of running the skimmer
during the time that the main tank is dark and the refugium is lit. My
understanding is that this is when the bugs stay close to the bottom of the
refugium and are not brought into the tank in large numbers. Therefore, the
skimmer would not be skimming the bugs during feeding time.
<A good idea, hypothesis to try out>
Would turning the skimmer on and off on a daily basis cause just the chemistry
changes I am trying to avoid? Does the skimmer really kill the plankton I have
worked so hard to grow?
<Systems can be co-opted, marginalized in either case>
What about Keep It Simple, Stupid. Am I going way overboard here. I feel that
the benefit of biodiversity and food source from the refugium outweighs the
cost of complexity. I'd like to get away with the algae/mud bed acting as this
refugium - I'm just not sure if the algae/mud bed will feed my Mandarins.
<Try it out>
Furthermore, I am afraid that the skimmer will become necessary as I add more
fish down the road but that's a complication as well.
<Yes>
That's about it, for now.
Thank you immensely,
-Jeremy
<Be chatting my friend. Bob Fenner>

Planning a Refugium Conversion
<<JasonC here, Bob is away on a diving trip.>>
Bob, I currently have a 125 gallon reef tank that I have been having problems controlling nitrate levels. The tank has been set up for about a year and a half so my water is well circulated. I do not
overfeed a do water changes on a regular basis. The only filtration I have is a home made trickle filter, a five gallon bucket full of about 3 gallons of bioballs that trickles into a 30 gallon tank, carbon inserts, and a Berlin protein skimmer. I have done some research on how ammonia becomes nitrite which in turn becomes nitrate and think that I finally understand the process. The sump and trickle filter are all new additions to my tank. I previously had 2 Emperor filters with BioWheels. If I understand the biological process correctly, the bioballs are not helping matters at all in trying to bring down my nitrate level. <<indeed, the bioballs make such an efficient biological filter for the first two stages [ammonia/um and nitrites] that the filter can produce nitrate ad nausea.>> I have been doing a little more research on refugiums and plenums and it seems that these ultimately are the cure for bringing down nitrate levels. After reading a couple of articles on the subject I have come up with a bunch of questions:
1. Is it possible to convert my existing 30 gallon sump into a refugium and a plenum? <<sure, just add some sand and live rock - plenum you can do without if the sand bed is deep enough, perhaps more than 4" deep if possible.>>
2. Can I remove the 5 gallon bucket with the bioballs all at once or should it be done slowly? Does it matter since my tank has been set up for over a year?
<<Slowly is best, probably more so because the tank is well established.>>
3. Is there anything out there that I can buy to initially get the refugium started? <<live rock>>
Thank you in advance for any help or insight you may have on this topic. Your website is a great help for everyone trying to preserve and capture a small piece of beauty that are coral reefs.
Gianluca
<<Glad you enjoy. Bob will see this and will appreciate the kind words. Cheers, J -- >>

Hey Bob ;) (refugium questions)
You are just a great aquarist and answer questions at times on the FFExpress
FAQ (a section I have read, I'd say, 85% of all questions and answers).
<You must be a vociferous reader! Please also see our site: www.WetWebMedia.com>
Anyway, I have a question about refugiums (a section that I believe should and
will become its own section on the FFE website FAQ). Going forward, I really
like the idea of a refugium to lessen possible nitrates and to keep PH swings
in check all while providing food for my tangs.
<Good purposes, possibilities all>
My system: 6 weeks old --> 75 gallon 15x24x48, Sump --> 30 gallon sump with
bioballs (all over flows and returns are in a trapezoid in the back middle of
the tank), UV sterilizer, Berlin protein skimmer, 150 watt heater (never on);
Natural filtration --> 90 lbs. live rock (FFE), 80 lbs. live sand (FFE), good
water circulation (all via powerful return pump and four return pipes), 96 x 4
PC lights (two actinics, two daylight), all cycled -- daylight 7 hrs day, 9
hrs actinic. My Parameters: Ammonia, Nitrite, Nitrate = 0, Temp swings from
77-81 during most 24 hour periods, Strontium and Calcium added periodically.
Livestock: Kole Tang, Hippo Blue Tang, One True Perc Clown, Two Banggai
Cardinals, 50 gallon clean up crew (FFE), 75 gallon reef relief (FFE), two
large cleaner shrimp, and one more sifting star.
Here's the deal, all animals are eating and adjusting nicely 1) I want more
animals: corals, anemones, and a few more fish. At this point, what do you
suggest is possible to be added without overloading the system in its current
state? 
<Please read through the "livestocking sections" on the Marine part of the WWM site and the many survey pieces and associated FAQs here... many, many choices>
2) Should I add the refugium now or later? 
<Now>
3) There is a place in my
sump that looks "just perfect" to me for a refugium. It appears that it would
be about a total of 3 to 5 gallons in volume. Is this big enough to have a
noticeable effect, and or a sizable refugium for 'pods and macroalgae? 
Or will
its effect be negligible?
<Worthwhile, noticeable>
4) Pending this is adequate (even though it may be
too small; assuming it will have a good effect none the less) in size, what
kind of lighting do I need (for the refugium)? 
Wattage and Type, if you will.
<Please read: http://wetwebmedia.com/refugium1.htm>
5) Do you suggest the 24 hour period of lighting, or the reverse light
period for PH swing minimization?
<For most cases, circumstances, continuous lighting>
6) In the small refugium tank set up, when
the water flows back into the main system, in my case the other portion of the
sump, should it over flow from the top of the refugium, as in skimming like in
the main system? Or doesn't it matter? 
<Mmm, sometimes does matter... here over the top will be fine>
I'd like the water to be pumped to
the top of the system and flow from a little below the water line to encourage
'pods to flow back to the main system for a possible mandarin dragonet in the
future (yes I know that most of the 'pods will be shredded in the return, but
I assume their remains will still become food for the mandarin, again if you
could address this assumption I'd also appreciate that too).
<You will be surprised to find how many critters make it through the pump mechanism intact>
Mr. Fenner, you are the best. Thanks so much for your help. Thank you
thank you thank you!!
<You are welcome. We are soon to be good friends. Bob Fenner>
Concerned "Conscientious Aquarist,"
Rich Walker

Re: Hey Bob ;)
You don't know what this insight and wisdom has meant to me and the innocent
marine life I have adopted! Not to mention lighting response!! Thanks so
much Mr. Fenner for your help. I will be in full contact with you on my
operations and my new refugium to be constructed and added this weekend! If
you are interested in pictures too, I will add them also! Talk to you soon,
and again thanks so much. The aquarium community owes you a great debt.
Rich
<Your effusive enthusiasm for life, the hobby and my small part in helping are... palpable to put it mildly. Thank you my friend, for boldly brightening my day. Bob Fenner>

Refugium
Bob,
Ok I made up my mind I'm going to add a 10 gallon refugium under my 240 gallon FO+ 100lb liverock tank. It will sit next to my wetdry sump. I have several questions, one is 10 gallons big enough??
<Bigger would be better, but even this small size will have appreciable beneficial effects>
I know bigger is better , but will it make a GOOD difference in lowering nitrates?
<Yes>
Second is it essential to have "live sand " as the substrate for the refugium? 
<No>
I plan on just using aragonite, the non living kind.
<It will become live of its own accord>
Third how many inches should the substrate be?
<A couple...>
Fourth how should the water flow/current be in the refugium? Should it be VERY calm?
<A couple to a handful of turnovers per hour are ideal>
Last question is the refugium should only contain Caulerpa, aragonite, and fluorescent lighting right? 
<Other things that might go in include live rock, "mud", other algae...>
Let me know if there should be anything else in the refugium. I plan on using this to battle my nitrates. I know there are a lot of questions that I ask, but I couldn't find the answers in the WetWeb media in the "REFUGIUM" section I read the whole thing. Thanks Linstun
<Take a look through the associated FAQs there... the blue links at the top of each Page. Bob Fenner>

Refugium article "get thee to a refugium"
Mr. Fenner,
I was curious about your article, get thee to a refugium. At the bottom,
under the heading "how to do it" there doesn't appear to be any text, just
light/dark, pumps/equilibrium, etc.. I was wondering if the article isn't
complete, or I'm missing something. I'd love to read about how to do it.
<Thanks for this note... will have to take a look/see further... there are whole article/installments on refugiums in a "pending" file (some years old) waiting publication (first rights...) for hobby magazines here and abroad... and what constitutes a manuscript/draft of a book ("the conscientious reef aquarist") not in print... so, some excuse for non-inclusion... a/sort of paradox of "making things known" versus crass (what am I saying, "necessary" more like it) need to "make a living"... will add this to the "Task List" (it's humongous) on FrontPage "to do" list to move more here... Any specific question/s?>
I have a 10gal tank now - I have a thing for small tanks, mostly the
footprint of where I want to put it. What I want to do is plumb it to a 50g
sump with a 10gal refugium in the basement - Just live
sand/rock/macroalgae. Maybe someday I'll tie a larger tank aka 75 gal into
the mix, but for now I like the stability of another 60 gallons so I can
stock the 10 with community (peaceful) fishes. Currently have a Banggai
Cardinal and a fake Percula.
<Sounds good, neat>
Thanks for your help, your book was recommended by the LFS, and that's the
reference I've used to get into the hobby. I had to chance a small tank
because I'm a student, and alas, anything over 12 is not allowed where I
used to live.
<I couldn't afford even this size system... so, I installed and kept them for other folks (and scratch) as an under-grad...>
But, suffice it to say, had it not been for your book, I'd
probably have the 10 stocked with comets.
<Nothing wrong with Goldfish.>
Thanks again!
Patrick Guffey
<Be chatting my friend. Bob Fenner>

Two level refugium
Hi Bob
It is a pleasure to ask a question as I always find my answers using
the Google feature. Have a 120 with 50 lbs rock, 2 in cc and 4 fish; 8
inch lion, full grown zebra moray, medium puffer, 2 in Achilles tang.
<Wow, two inch is small for this species in captivity>
Just ate my 12 inch panther grouper for dinner (tasty) who accounted for
about 1/2 the bio load food) and put in the tang (4 weeks in the main
tank I am hoping to get lucky with this fish). I have had the first
three fish for 2 years now and have never had a fish die Would like to
grow some coralline algae and liven up the rocks so I'm changing
things. This tank will ultimately be a reef once I can afford a 180
of. I have unlimited room in the 3 foot crawl space under the house
where my wet dry and urchin skimmer are located.
<How nice.>
Just took out half of
the BioBale and will dump the rest soon at your recommendation. Saw 30
gallon Rubbermaid tubs at home depot today and was thinking I would use
2 of them for a refugium. 
<Sounds great>
Should I do a plenum in one (which one?)
<Good idea, the second... or just one if run in parallel (versus in series) that has the slower flow rate of water through/over it>
and
rocks and macro in the other or keep both the same. Originally I was
going to put 1 inch sand, rocks and macro in one big tub. I have no
experience with invertebrates other than growing tangs delight in a 20
gallon for my Achilles. 
<Algae, not invertebrates...>
Also, would a calcium reactor benefit my
situation or should I wait for the reef. 
<Would benefit... you could make one... would really boost your corallines... but not necessary>
I have not done a single h2o
test in over a year and do monthly 25% changes. I would like to take
this tank to another level.
Thanks for the fantastic service you provide with the q & a.
Sean from Denver
<Thank you for writing, sharing. Be chatting. Bob Fenner>

Idea for refugium
Mr. Fenner,
thank You so much for the time you spent educating the novices like myself
about the marine world. 
<A pleasure, honor and duty I gladly undertake>
I have a 55 gal reef with a wet dry filter,
skimmer, and UV. I also have about 35 lbs of live rock, and a light
bio-load (4 small fish, a yellow tang 2 shrimp, a Condy and a bubble coral)
would it be OK to remove the bio-balls from the wet dry or should I add more
LR?
<Both or either>
My next ? involves the use of a refugium. I was wondering if I could
drill a hole in the side of my wet dry to act as a overflow into a
Rubbermaid makeshift refugium?
<Yes... a good plan for increasing volume, flexibility...>
this would allow me to move my return pump
into the refugium, and allow me to use my wet dry as a sump for the UV and
Skimmer. I was wondering how big Rubbermaid container would have to be. 
<Hmm, about as big as you can fit. There are a bunch of handy sizes, types available>
and
could I use my submersible pump in the refugium????
<Yes>
thank You. Be chatting Jeremy
<You're welcome my friend. Bob Fenner>

Refugium Feasibility and Set-Up
Hi Bob,
You may recall that I am the person with the 300 gallon reef tank, live
rock, live sand, plenum etc. who asked some Angel compatibility
questions . . . It has two overflows, one on each end of the tank with
sponge filters in each to trap the grossly-large particles, which flow
down into the cabinet to a wet-dry sump. I have a pump which then pumps
to a "T" to returns that are on each end of the tank.
<Good description>
I was working on my plumbing today, cleaning the filters and adding some
decorations. When I killed the power to the pump, the sump
over-flowed. That told me that my sump is not big enough, right?
<Yes... and/or your water level was too high in the main tank, and/or the overflows not made "high enough" and/or of sufficient through-put/diameter... Best to set all up "as if it were running", turn the power off, and see how high the water comes up in sump... or alternatively to start with the system turned off, fill the sump "all the way", turn all on and mark the low spot where the water ends up in the sump, use this as a guide for the maximum fill...>
I have always been intrigued by the idea of a refugium. Quite simply, I
would like to grow food -- algae and micro-critters -- for my tangs and
sand-sifting gobies to munch on. I don't need a plenum, because the
main tank already has one.
<Okay>
If I bought a new and larger sump -- and hung some appropriate lights
down in the cabinet -- could I simply put the old sump next to the new
one and use it as a refugium? 
<Sure... divert "some" (a tankful or two) flow to it per hour... have "flow over" to the main sump...>
Would the full capacity of both sumps be
available for plumbing drainage when the power is off?
<Mmm, not really... if you rely on gravity to more the water from the refugium to your main sump... you could get a bit more leeway by reversing this order (have a small pump move the water back to the main sump and the replacement water overflow back into the refugium via bulkhead/plumbing connection/s... Is the gallon or two here worth this? Non IME/HO... Again, experiment with turning pumps off with sumps full... and consider modifying the overflows in the main tank...>
I read your book, web site, and FAQs on refugiums. The book made
passing comments, the web site page is not complete and does not explain
how to do it, and the biggest comment you made in the FAQs was to do the
refugium "in parallel, not series." 
<Yes... to try and be more clear here... For you to cut in a "Y" with a valve going to the refugium, to adjust the smaller flow rate there... and have that water (in the refugium) course over to the main sump for processing, return to the tank... Not in series as in ALL the water going from the tank, through the refugium, through the sump, back to the tank.>
With that, here is my idea: Can I
have one side of the tank (overflow A) go down to the old sump/refugium,
and immediately be pumped back up to the return on that side . . . And
then have the other side of the tank (overflow B) go down to the new
sump -- which would have the activated carbon and the protein skimmer,
to be pumped back up to the other return? In effect, one side drops
water down to the refugium and to be pumped back up with food, and the
other side drops water down to the new sump to be filtered and pumped
back up nice and clean.
<Likely there would be way too much flow to/through the refugium in this scenario...>
Let's say this idea works . . . Here is the next question, maybe a
stupid one: How do you keep the pump in the refugium from pumping sand
and dirt back into the main tank?
<Mmm, set it/the pump up high enough to where these materials aren't in that part of the water column? Use particulate filters? Baffling to drop out much of this material?>
Many, many thanks!
Dale M.
<Clarity is pleasurable. Bob Fenner>

Refugium
Hello Mr. Fenner,
I just wanted to ask if in my last email you saw a
picture of my sump (I attempted a drawing) that looks
like the one the you posted on your daily Q&A? Because
if you did, that was way off!! :)
<Yikes! Did see it... it's a work of art in "my book"... You're a much better e-artist than I>
Maybe yahoo and hotmail have a strange format change
because that looks no where near what I drew.
Ahh.. dang. I hope you saw what I wanted you to because
your answer might have been based on the wrong idea.
If you could let me know, that would be a good thing.
I won't go to my hardware store and start buying away.
:)
Thanks
<Do think I have an awareness of what you are/were getting at... and your refugium design is fine. You can see it posted on the Daily FAQs today: http://www.wetwebmedia.com/dailyq&a.htm
and will be moved to the "Refugium" section of the marine index on the morrow.
Be chatting. Bob Fenner>

Refugium
Hi Mr. Fenner,
Thanks for the quick reply. I asked about a refugium
on the center glass divider of my tank. I kind of knew
in the back of my mind that it would not be the best
idea. I have decided to cancel my skimmer order to an
AquaC the uses a pump placed into the water.
This will allow me to have the refugium in my sump. I
am having a hard time visualizing how to set this up.
I have a rather bizarre sump that was sold to me by my
LFS. I will attempt a diagram below..

water out water in
___________I__I______
I___________I__________I__I______I I= acrylic wall
I IXXXXXXXXXXXXXXXXXXXXI X= Bio Balls
I IXXXXXXXXXXXXXXXXXXXXI ~= water level
I IXXXXXXXXXXXXXXXXXXXXI
I IXXXXXXXXXXXXXXXXXXXXI
I~~~~~~~~~~~I I~~~~~~~~~~~~~~~~~~/
I___________I_I_________________/

Okay that is a rather base drawing at best. I will
remove the bio balls and add coarse & fine sand as well
as smaller live rock & macroalgae.
<This sounds good>
On the left side I have two pumps 1) return to the
tank & 2) to supply the skimmer
I would raise the water level to half way to the top
or slightly higher.
<Do "practice" how high this water level should be, by filling the sump with the power off to your pumps... turning on and seeing how low the sump gets to... this is your high water mark there...>
What do I do to make sure it does
not overflow if the power goes out (I have an overflow
to provide water to the sump)?
<Ah, see the above or: http://www.wetwebmedia.com/pbfaqsmar.htm>
Also another question
is at the top of the sump where the water comes in, it
first goes across an egg crate. Could I leave that in
and put the lights on top of the acrylic? Would it be
able to get enough light? As far as lights I have
heard good things about home depot outdoor PC lighting.
I would like to use that if it would fit.
<Yes, it should>
If that would not be a good idea what would you
suggest as a lighting setup?
<Please check the e-tailer links on WWM>
I am drawing a big blank
there. :) If you could give me some ideas I would be
so grateful.
Thank you so much! I am sorry for the long post, I do
not want to ask too much of you! I do hope I was clear
about my questions.
<No worries. Bandwidth is cheap. Bob Fenner>

A refugium idea
Robert Fenner,
Hello. I hope all is well with you. I was hoping to
get your opinion about an idea I have for a refugium.
I have a 75 gallon tank with a 30 gallon sump. All is
well but my nitrates are on the rise. I want to build
a refugium. My space down below in the sump will allow
it but I wanted to upgrade my skimmer to an in sump
AquaC. That would take up all of my space there.
I have an idea but am unsure if it is at all
feasible. I have a canopy that is 10" high with 380
watt PC lights. My tank has the glass support in the
top middle of the tank. I am guessing that supports
the construction of the aquarium. 
<Yes>
Anyway, what I would
like to do is place a clear container like one would
find at Home Depot. and place some LR and Caulerpa in
that container. The light for the main system would
give to my refugium. How I would set up the plumbing I
am not so sure of right now. I guess I am just in the
"what if" stage.
My concern would be the weight on the glass divider
(thinking 10g)
<Mmm, this is likely "a bit much"... seawater weighs about 8.2 pounds per gallon... and the container, rock... will add some more per that volume... perhaps a handful of gallons... and then, what about the "shadow" of blocked light in your main tank... I would still look for space in the existing sump (doesn't have to be much) for rock, light, and macro-algae, or a way to scrunch in another container below, to the side... to run in parallel>
and if the refugium would cast a
harmful shadow to the center of the tank. I am going
to post this idea on WWF and see if I can get some
feed back there too.
<Good idea>
I would really like to hear what
you think and if you have an concerns with the
placement or possible plumbing & or lighting problems.
If there is something harmful right in front of my
face (that happens all too often when I am excited
about a new idea) I would like to know
Thanks!!
<Thank you for your well-thought out, written note. I think you will find another alternative to the center brace placement is more workable. Bob Fenner>

Refugium Questions
Howdy Bob,
<Hello Ben>
Let me start with a little background. I have a 55 gallon tank
that currently is home to 1 blue damsel, 1 false clown, 1
neon goby, 1 Hawaiian yellow tang, and 1 sebae anemone, as
well as several snails. It has a 2 to 3 inch bed of live sand,
and about 15 pounds of live rock. This system has been up
for a bit over 6 months now, the only recent addition being the
anemone a bit over a week ago.
<Okay>
On the equipment side, this past week I purchased a 48 inch
SmartLite. I have a hang on tank filter system that consists of 7
chambers I will attempt to describe. An in tank over flow feeds
a chamber that has the heater, safely away from all the little fishes,
that flows into chamber 2, where I currently have a sponge to catch
large debris that may enter the filter. From there, chamber 3
fills to overflow into chamber 4, the skimmer chamber. Water
exits chamber 4 via the bottom and fills chamber 5 to flow into chamber 6.
Chamber 6 has a 2 inch row of bio balls on top of some more
sponges. Water leaves chamber 6 via the bottom and chamber 7
has a powerhead to return water to the main tank. Pretty simplistic,
effective, and more importantly, nothing on the ground. I am
also a ferret owner, so trying to hide anything near the ground is
futile.
<I understand>
More background, while my skimmer does produce foam and some goo,
it has never produced enough to collect. My water is perfectly clear
and my fish seem happy and healthy. My only bane has been nitrate.
It seems to always be climbing rapidly. For this reason I am considering
a refugium, and I am slowly moving to a reef system and would love the
other benefits refugiums can provide. My to-do list for the next month is
adding 45 pounds of live rock to the system and a reef relief cleanup
crew from ffexpress.
<All good moves>
The goal for the refugium is better nitrate management and food supply
for future corals, inverts, fish.
<Yes>
Now on to my questions. Because of space constraints, I am considering
3 options.
1) Converting my current wet/dry area into a small refugium, basically
macro algae only.
2) Leaving my wet/dry area intact, and adding a CPR Aquafuge 18.
3) Adding the CPR Aquafuge anyway, and still utilizing my wet/dry
area for refugium duty.
Which of the 3 options would you recommend for a reef system.
<Number three>
I know you say the larger the better, but is giving up the wet/dry
worth it? And with such a light fish load, should I be concerned
about the lack of output from my skimmer?
<No worries>
Thanks for your time and knowledge.
Benji
<Glad to share my friend. Bob Fenner>

Sump/Refugium questions
Mr. Fenner,
I have attached a Word document with a picture of my sump and some questions. I would greatly appreciate it if you could take a look.
<A nice diagram/drawing... Do think the series of baffles will/would lend structural integrity to this sump... A few comments re possible changes: I would either place the pump in the second chamber, or make the first chamber (with the skimmer pump) a "spill over" (rather than under), to supply about the same "head" or height of water to the skimmer pump, to make consistent its delivery to the skimmer itself... otherwise, with the water level going up and down (with total water volume in the system) the skimmer will operate more erratically. 
I encourage you to actually "take out the two middle baffles and move the last one to just containing/surrounding your intake fitting for your return pump (do some checking on the "Quiet One" pump... this product (modified Grundfos) used to be notorious for having problems), build a contrivance above this intake area with the baffle to support mechanical filtration (to practically keep stuff out of the pump), and a tray for bags of chemical filtrates, pads... should you find yourself using such... And the intermittent area (the middle of the sump), consider placing more live rock... perhaps a mud base... live macro-algae and some simple illumination above. Much further sump and refugium input here: http://www.wetwebmedia.com/refugium.htm
and the linked files beyond. Be chatting. Bob Fenner>
Regards,
Don Mack

In-sump refugium
Hi Bob,
I am a fellow San Diegan and have been reading your book. I have found it to
be very informative and refreshingly practical. Thank you. The following
is a description of a future tank set up, followed by some questions.
I am planning to set up a 125 gallon marine fish only main tank in about a
year. The main tank will include some live rock and about one inch of sand,
a mixture of aragonite and "live" sand. I will connect the main tank to a
large sump, likely a 55 gallon tank if I can find a deal on a used one. I
intend that the sump will be sectioned off in two sections. One section
will be devoted to a refugium. The other section will be devoted to water
clean up. 
<Good ideas... the larger the sump... the better for sure>
I'm thinking that the main tank water will drain directly into the refugium
section of the sump. There, the main tank water will be subject to only
gross mechanical filtration, if any mechanical filtration is used at all.
Also, I am thinking that some of the refugium water will be filtered through
a fluidized bed filter to minimize any ammonia spikes that might occur in
the system. I am planning to grow macroalgae in this refugium to lower
nitrate levels, using full spectrum fluorescent bulbs. 
<Okay... though I doubt that you will need the fluidized bed as an adjunct to aerobic nitrification... and do look into the current Compact Fluorescent lighting technology for your system... Custom Sealife is here in town as a source... and do consider also coming out/joining with the local SDMAS (Marine Aquarium Society), a nice small group of outgoing types!>
The water would then flow from the refugium into the water clean up section
of the sump. This section of the sump will likely include a 100 micron
filter sock, a protein skimmer (most likely a venturi or needle wheel
skimmer), and some bagged carbon. The water will then be pumped back to the
main tank.
It would be great if you could comment on the following questions:
1. Would you mechanically filter the main tank water before it enters the
refugium? I could see how some people might think that the refugium algae
and bacteria (and any other inhabitants) would naturally process waste
materials from the main tank, and therefore, no mechanical filtration would
be needed.
<I would probably arrange for the eventuality or elective use of mechanical filtration... though after a few months of operation, particularly should you avail yourself of "mud, illuminated, algae filtration" it will probably be superfluous>
2. I understand that a drawback of fluidized bed filters is that the
bacteria colonized in the filter can quickly die if there is a power outage.
Are there any fluidized bed filters on the market that are less prone than
others to bacterial die-offs during power outages?
<Not really... you can always get/use a UPS product, maybe run that part of your system on a low energy use air pump... for real or back up... once again, I doubt if you will need, want to run such a device (FB) on an established reef.>
3. Is 2-3 watts per gallon of full spectrum fluorescent lighting sufficient
for growing macroalgae?
<Yes, most... for such a deep system (stock 125's range from 20-24 inches in depth if memory serves)... CFs or even some MH lighting might be a good idea... or perhaps some similar wattage fluorescents of whatever kind on 24h/d on your refugium and a modicum of the macroalgae situated there>
4. Would you incorporate a plenum system in the refugium? I have heard
contradictory stories about the plenums discussed in Bob Goeman's book.
Specifically, the most concerning thing I have heard is that plenums can
produce toxic hydrogen sulfide gas, which can kill all the tank inhabitants
in a single swoop. Why do people have problems with hydrogen sulfide
production in plenums? What kinds of things should one do to avoid the
production of hydrogen sulfide gas in a plenum? If one is committed to
growing algae in the refugium, are the drawbacks of the plenum significant
enough such that it would be prudent to simply focus on algae growth to
reduce nitrate levels?
<This is a BIG topic and still one of heated controversy... Properly set-up plenums and maintained systems with them rarely have these sorts of anaerobic difficulties... however, I am a big proponent of only utilizing such devices out of the main/display system for ease of manipulation... I would not be dissuaded in your case... but will broadcast our mail here to the local club for elucidation>
5. What do you think about utilizing deep sand beds in a refugium instead
of a plenum? I understand that Bob Goeman's states in his book that deep
sand beds will have anaerobic zones, which lead to the unwanted production
of ammonia. Yet others in the business seem to swear by deep sand beds.
<"Six of one..." both can be trouble... by and large, with the practical size of systems, grades of substrates folks use, this is a minor matter, let's say compared with not maintaining the beds themselves (periodic vacuuming, stirring...)>
6. Many people suggest using an ozone generator or a UV sterilizer to
"sterilize water." I am swayed by the benefits of ozone use as discussed in
your book. However, some people have told me that many hobbyists have
killed all of their tank inhabitants by having a mishap with ozone. I
suspect that they pumped in too much ozone. Some manufacturers recommend
using about 10 mg of ozone per 25 gallons of water, and I was thinking of
sending this amount of ozone through the skimmer on a constant basis. Would
you recommend this amount of ozone on a constant basis? Would less ozone be
more prudent for use on a constant basis?
<Such urban myths of "dangers of ozone" rarely amuse... The production units available to hobbyists are incapable of such mortalities... if lucky they'll move pH slightly, of discernible effects... While improving water quality greatly. Yes, all the wholesale, collector facilities I have been part of design, construction, operation have utilized ozone, ozonizers... generally feeding the source into foam fractionators and running continuously...>
Thank you in advance for any comments. I apologize if the length of this
email message took up too much of your time.
Bruce Grant >>
<No worries. Do take a look at our website for more collection of others opinions/input of a myriad of topics: Home Page , the local club: eGroups : SDMAS 
and hope to meet you someday.
Bob Fenner>

Re: In-sump refugium
Thank you for your prompt reply, Bob. I'll take your advice and look into
the SDMAS. Just two follow-up questions with regard to our discussion:
1. I was thinking of using a fluidized bed filter because the main tank
will be devoted mostly to fish, and hopefully a fair number of them.
Accordingly, I thought that ammonia production could be an issue and a
fluidized bed would help. Knowing that the main tank will be devoted to
fish, do you think that the refugium could keep up with the ammonia
production levels? If more biological filtration is needed, would you
recommend another type of biological filtration other than a fluidized bed
filter?
<Hmm, do agree with your approach. Large, vacillating amounts of nitrogenous wastes are handled never better than by fluidized beds... just that they also produce quite a bit of nitrate... and are often unnecessary in a fully up and running system, heavily fish-weighted or no... But no big problem... you sound as if you will way on top of the goings on in your system... and can always turn it off if/when you find your live rock and sand are doing all that needs to be done that can by FB use>
2. Would you mechanically filter the main tank water before it enters the
refugium? I could see how some people might think that the refugium algae
and bacteria (and any other inhabitants) would naturally process waste
materials from the main tank, and therefore, no mechanical filtration would
be needed. To reiterate, I intend upon mechanically filtering the refugium
water through a 100 micron sock before the water leaves the sump and enters
the main tank.
<Probably not, and sorry to have missed this item in our last tete a tete.>
Thanks again, Bob. >>
<You're certainly welcome. Bob Fenner>

Refugium
Mr. Fenner,
I have read your book The Conscientious Marine Aquarist and I believe it is one of the most informative books on salt water aquariums. I would like your input on a refugium for my 70 gallon tank. the only place to put it in my application is under the tank. I have a hang on the tank protein skimmer. The tank is full of live rock with live coral that seems to be flourishing.
The question I have about refugiums is what size tank? How much water flow to the refugium? What type of lighting is required for the refugium?
I hope you can give me some advice!
Thanks, Parke Harber
>>
Thank you for your kind, encouraging words. The refugium should be as large as possible/will fit, compact fluorescents are the preferred lighting method, and two, three times flow per hour through the system's about right.
Pls see more stored on our site: Home Page concerning this issue.
Bob Fenner

Refugium
Hi Bob,
Hope you enjoyed your trip and got some good rest.
<Thank you. Very nice battery-recharging so to speak... and very nice folks in the Cook Islands>
I want to get your advice
on a refugium I'm planning to set up. My goals are:
1. Main tank algae reduction.
2. Live food production for fish and invertebrates.
3. Water movement/ wave generation.
4. Water chemistry.
<All worthwhile, and attainable>
I don't worry much about the 4 point because the water in the tank has been
good so far, and I'm planning on adding a Calcium reactor later that will
hopefully cover that (By the way, won't calcium reactors act as fluidized
beds to some extent?)
<Yes, and vice versa... given large enough areas, patient monitoring and time (ahh, that all important, ever-elusive ingredient)...>
 I plan to make it with 3 chambers. The first two
would be only divided by a grid that would let the water pass between the
two.
In the first there would be a bed of mud (miracle mud?)
<Maybe... could be just live rock, substrate of some sort (likely carbonaceous)... and can be added "later">
and I will grow
Caulerpa in it. I plan on putting one of those plant bulbs on top of this
that will remain on 24 hours a day. The water will enter the refugium on
this side.
On the middle chamber there will be a bed of 2 - 3" of live sand, and on top
of it as much live rock as I can cram in there. The purpose of this is to
grow as many stuff as I can to have the fish/corals happy and full of eating
whatever this produces. If you know of any way I can max out the "live
stuff" production here it will be greatly appreciated, Stuff like what to/not
to-put in animal/plant wise,
<I'd actually place no animals expressly here... i.e. none of the so-called "cleaner uppers"... some may be useful down the line (months)... but the "real" organisms will come about, live (not be consumed, outcompeted) by way of introduction through the macro-algae like Caulerpa, rock, sand...>
or any better way besides LR/LS or mix of them
or anything you think might help produce significant amounts of creatures.
Then there will be a divide that will not let the water flow but on the top,
sort of an overflow wall. The water will fill the two first chambers, and
overflow onto the third, which I plan to use as a surge device, this way any
live stuff won't be forced to pass through any pump.
<hmm, do us both a favor and supply at least a small slot to allow some water to "underflow" the last section... should your water level "get" too low in the sump/refugium... at least this will save your pumping mechanism... maybe the life in all... And don't be overly concerned about the biota getting "spliced and diced" too much if/when it passes through the pumps volute/impeller... much will get by just fine>
One thing is that I
don't want bubbles in the main tank because I want to have sponges/sea
squirts. I plan on having a sort of modified WC reservoir valve (Funny ha?)
<Not humorous at all, a very good idea and description>
that will close before all the water pours out, and that way will (Hopefully
) keep the surge pipe filled with water so it wont introduce air bubbles in
the next surge. There will be a 1.2 - 2" pipe that will direct the surge
against the normal current in the tank, and a 1" pipe that will be a safety
in case the valve won't open.
<Maybe situate a bit of coarse plastic media there as well to aid in this "bubble busting" exclusion... the Fein and Grob flocken that Eheim makes/sells is excellent here... one time purchase>
And last, I plan on building a tall wood canopy that will also hold the
refugium 2 - 3 feet above the tank. I'm still thinking how I want to build
this because I know it can be a problem to access the tank, and will not be able to take it off because of the weight of the refugium.
<Read through, consult with carpenters in your area... or a friendly structural engineer... there are fasteners, cabling systems that will greatly help in lifting your canopy, keeping it out of your way while working in the main system... and a need for careful design of the support of your refugium (that can "just" overflow via gravity and a constant level siphon/box back into the main tank if it's situated above it>
Please advice
also on size of the refugium tank (20 gal-30 Gal...) so it can hold all that
stuff; how to much space give to each chamber; and advice on a good pump to
get the water to the refugium. I'm including a rough scheme of the thing in
an attachment.
<twenty, thirty gallons ought to do it... and the structure... take a look at Leng Sy's pix in the hobby mag.s for Ecosystem Aquarium's acrylic boxes... they're about the right dimensions...>
Thanks a lot for your help,
Norberto.
<< Refugium.jpg >>
<Be chatting, Bob Fenner>

New Refugium
Dear Bob,
The progress of my reef may be among the slowest on record (if there were records). 8 months and still only 5 fish and one coral with 130 gallons of water. 
<Best to go slow my friend... the reefs in the wild take much more time than this...>
The yellow tang comes Monday and the dip and quarantine tank are ready. The flame angel is bought and hanging out in a dealers tank until I get the tang situated. Maybe I'm slow and my basement filtration system is over done but I still haven't had a sick or dead animal.
<Very commendable>
I have put together a 20 gallon (net) acrylic box for the refugium. It will be drilled for an overflow into the main sump through a filter sponge (to catch bubbles) and fed through a ball valve with 0 to 200 GPH from the 25 micron mechanical filter. Two 20 watt "daylight" fluorescents for lighting. 15 pounds of small junks of live rock with a good start of both grape and blade Caulerpa are ready in a spare tank.
<Very nice... though the mechanical filter is somewhat unnecessary>
Even after reading most of what I found with "Google" (another fantastic service from wetwebmedia! ) I would value your answers or opinions on a couple of questions.
<Okay>
I have sand and gravel aragonite material. Which should go in the refugium? Or both?
<Both or separate would be/will be fine... if it were me/mine, just the larger grade Aragonitic material for ease of cleaning...>
How can I "inoculate" the substrate? The only live sand I can get in small quantities comes in prepared jugs or bags of liquid. Does this have worms and copepods? Should I take sand from the mature show tank?
<It already is, will be from the live rock in your main system... just bypass that 25 micron sieve for a few days...>
Should I add an air stone? A small powerhead?
<No... the flow and algae that will grow there will do all the gas exchange needed, desired>
When I get this going I will have over 160 gallons in circulation. Does all this "count" when determining acceptable bio load?
<Of a certainty, yes>
Between dive trips, I am really enjoying this great hobby!
Howard
<Wish we were in some place with warm, clear water right now. Bob Fenner>

Refugiums... and beyond!
thanks to your writings, I was inspired to investigate refugiums, and have
found a LFS that can get compact versions that will work perfectly with
both of the systems I have, I only wish I did this a long time ago, thanks
for the help, tom
<You're welcome my friend. Life to you. Bob Fenner>

Need your advice.. (refugium re-design)
Bob,
hope all is well with you.
<Yes my friend, thank you>
I wanted to get your opinion on using a CPR Aquafuge
Refugium with some Miracle Mud and Caulerpa on my 60
gallon fish only tank.
<Both good products, approaches, compatible>
I would love to get my hands on an Ecosystem Filter,
but I felt I could save myself some money by doing it
this way. Plus, I didn't want to just do away with
the wet/dry filter I am using.
<I understand... and have seen, used many such "modified" systems myself>
Do you think this refugium would work or do you think
I should spend a little and pick up an Ecosystem
Filter?
<The system you propose will be fine. Bob Fenner>
take it easy,
Dindo

Re: need your advice (refugium modification)
Bob,
I appreciate your help as always... hope your
Indonesia trip went well...
<You're welcome and thanks, yes, very enjoyable>
have another question or two..
how can I add this CPR refugium with Miracle Mud and
Caulerpa to my existing 60 gallon tank without
bothering the livestock and water chemistry?
what do you recommend I do?
<Hang on the back, fill with system water, add mud, rock, algae, let settle for a week or so with the lighting on... then turn on the pump>
do you know where I can get some compact lights to
light up the CPR refugium?
<Probably easiest to order from an e-tailer as an intended pet-fish product/hood... list on WWM links pages... or make yourself with fixture/lamp from Home Depot, Lowe's sort of outlet>
or what other type of light would be beneficial?
<I would use small compact fluorescent... that's what we use on ours>
much thanks, Dindo
<You're welcome. Bob Fenner>

Refugium
Bob,
After a recent visit to your site, I realized that I may be confused about optimum refugium configuration.
<Let's try to straighten each other out>
I currently have a conservatively stocked 100 gallon tank in circuit with a 55 gal refugium. The refugium has live sand over an under gravel filter plate (without circulation), live rock, multiple varieties of macro algae, and many varieties of worms, and crustacean-like creatures. It is isolated from the tank with a 25 micron filter in the return line. The setup has been stable for 14 months, with no apparent disease (except the two hippo tangs with HLLD that they developed when in isolation and Rx for parasites, probably scars as no other fish has similar symptoms).
After reading on the site, I reversed the light cycle on the refugium (now 4pm - 10 am).
<Good idea>
1) I have left the gravel in the refugium undisturbed: some references on your site implied that I should clean it periodically. Should I do so?
<I would at least "gently stir it" once a month... to increase circulation, discount compacting... or gently vacuum one half each period/month>
2) Should I remove the mechanical filtration in the return line? Is there any concern about losing the property of blocking parasite life cycles with the filter? Would it be better to allow the crustaceans in the refugium to be pumped into the fish tank?
<I would leave out the particulate filter. Bob Fenner>
Thanks!

Carefully planning the expansion of my reef
Hey Bob,
So you have answered all my questions about refugiums and the like directly and indirectly....
I am NOT making the same mistake I made when I got into this hobby and just jumping in with little research :)
<Plenty of time now... and more than enough new mistakes, omissions to make w/o revisiting the old ones>
So before I set up a sump/refugium type deal I want to make sure I am solving MOST issues at once and not limiting my solutions by taking a particular path....
I want to make this reef a little more self sufficient. Already I see that adding chemicals, such as CA and trace elements will become expensive and a burden, worst I could neglect it and that would not be fair to the residents of the reef :)
So that being said, I want a Ca reactor...
<Good idea>
I don't know if you are not permitted to give brand name recommendations but I am asking anyway :)
<Yes... it (this site) is of my creation, origination... can/do say pretty much what I think, feel... a few brands are fine, Knop, K2R... and there is sufficient help to consider DIY... see the link to Oz's Reef on the WWM links page>
I only have 20 inches in the refugium/sump to fit it...
<You mean within the stand? An important consideration... some will fit... or you can place the unit outside of the stand, delivering the effluent via a line that drips into the sump>
I am beginning to think that I will have no room for the refugium part if I put a skimmer and a Ca Reactor in the sump side. The tank will only be say about 10 gallons of water in a 20 gallon tank. I thought that I had room for a 27 gallon but then I would not have room to put my hand INTO the tank to do stuff.... I might get a custom one built to the maximum dimensions of under my cabinet... spent too much already to skimp now :)
<Or perhaps a more flexible container and through hulls fitted with flexible tubing... Like a Rubbermaid tub?>
Ok, So what Ca reactor will suite my needs with the space limitations and a 108 Gallon Reef tank.
<Do take a read through a recent issue of FAMA (Freshwater and Marine Aquarium Magazine) and/or the manufacturers listed on the WWM links page here. I haven't reviewed what's available in several months>
Other specs:
108 Gal
173 Lbs LR
160 Lbs crushed coral
5 Powerheads
440 Watts VHO
Fish and inverts and corals (Anemone, Green brain, Colt Poly, mushrooms, Bubbles, etc)
SeaClone skimmer I am dropping (well want to anyway)
for a AquaC or other... again space restrictions... Euro-reef would fit too...
So what do I need buddy anything else?).... I want to get it right....
I guess everyone does.. that is why we write you :)
<Just the gear that goes with the unit... a carbon dioxide bottle, regulator, needle valve, controller if you really want one...>
But don't worry. I have not stopped using my own head and won't rely COMPLETELY on you... or will I, hehehehahaha:)
<Now you're worrying me!>
Kind regards,
Robert Jackson of Canada....
Fun FAQ's
Yes people use chillers in Canada too :)
<Be chatting. Bob Fenner> and...

Ca Reactor cont'd
Hey Bob,
I have to leave work and was too lazy to reopen hotmail :)
How about this reactor... sounds impressive...
C-1502 KORALLIN KALKREAKTOR
Regards,
Robert Jackson
<Yes, a good unit. Bob Fenner>