Refugium Sizing

[GaryP]

I'm planning on adding a refugium to my 125 gal. system. What I'm trying to figure out is how to size it. For a couple of reasons I can't put it under my tank and I'm planning on putting it on a stand next to my tank. The good news is that it will be next to a window and should get some extra light.

I won't need to put my skimmer or bioballs in the tank. All I really need is a place to grow some macro, and the accompanying benefical critters of course. I raised the question yesterday at the meeting and the general response was "as large as possible." Is there a rule of thumb or ratio for sizing a refugium?

Gary

[witecap4u]

Like everyone else said as big as possible. I think the smallest you would want to go on a 125g is like a 20g.

[TexasState]

I used a 20G Tall for my 125 b4. If I can do it over again, I would go with a 30L, 40Breeder, or 55G. Are you sure you can squiggle a 30L under your stand?

[GaryP]

I can just barely get my pumps and skimmer in the 30L sump that I have there now. Hanging a light under there would be impossible.
Buiding a new stand would make this little project a bit more than I would want to take on at this time.

Gary

[alexwolf]

i am currently using a 20 gal tall.........under a 135, paired with the sump it works pretty well, i did squeeze it under my stand.....

[matt]

Gary;

In terms of supporting a given quantity of macro algae, there may in fact be size limit. I think the question here is basically how much caulerpa will a 125 gal system support in terms of nutrient production. I have no idea. I know Julian Sprung had a nano reef attached to a much larger refugium, but i think he mostly used mangroves rather than caulerpa. You could do something similar, or maybe grow sargassum rather than caulerpa; you could even have a sea horse population in the fuge. That's what John Moffett did, I think, and it looked great. Of course, you could have as large a refugium as you wanted; but you may not be able to fill it entirely with caulerpa. I don't know; maybe a typical 100 gal reef tank could produce enough nutrients to support a 500 gal caulerpa tank; maybe only 50 gal?

If it were my tank, I'd consider setting up something based on what it looked like; if your 125 is 18" front to back and 24" tall, I'd look for a tank that was 18" long, 24" tall, and mount it "sideways" next to your main tank. I'd also want the water level in the refugium a few inches higher than in the main tank, so you could gravity drain into the main tank. Sounds like a fun project to me!

[GaryP]

Matt,

Yea I was thinking about sea horses, or even pipefish. I've been wanting to do a nano seahorse tank. This may kill two birds with one stone.

Gary

[captexas]

Gary -
As it will be next to a window, mangroves would be great. Problem with mangroves in most refugiums is that once they grow to the level of the light over the fuge they stop growing or get burned by the light. Only problem I see of having it next to a window is the sun/outside heat heating the water to unacceptable temperatures.
As far as sump size goes, the greater the overall water volume the better. Many people have sumps as big or even bigger than their display tanks. I have a 75gallon display tank and I built an acrylic sump that is 36in x 24in x 24in, 75gallons if filled completely. I built a refugium into one side of it that is about 18in x 20in. Works great.

Chris

[GaryP]

I do have a spare 50 gal sitting around but I would have to build a new stand to get it high enough to gravity feed to the 125 gal. What would be the downside to having it gravity feed to the sump?

I thought of the problem of having the mangrove grow into the bulb. Seen that before. I was thinking of a pendant that I could raise, but then that would reduce the light intensity to any macros I have growing in the fuge. I need to work something out to make this project "attractive" enough that I'm not going to catch hell from my better half.

Gary

[GaryP]

OK, scratch the 50 gal. idea. I just measured and there isn't enough room. I think I'm going to go with a 30 gal. long. I know of a cichild breeder that has a whole store room full of them that he bought at auction at the shrimp farm in San Marcos that went belly up.

Gary

[matt]

Gary;
The advantage of having the refugium gravity feed to the main tank is that any critters from the refugium that you want to make it to the main tank will not have to go through a pump impeller to do so.

[GaryP]

Duh! Thanks.

[Instar]

Its funny to say the sun will heat a tank by the windows. That little bit is nothing compared to the MH or even PC's. My 125 is in front of 10 feet worth of windows. Highest water temp is 83.

[GaryP]

Larry,

I don't think I'll get a lot of direct sunlight anyway because of the position of the window, a wide eve (sp?), and trees outside. I'll take what I can get though. I'll take all the "free" 5500 K I can get.

Gary

[captexas]

Larry -
I'm not sure what is funny about it. Just because your tank doesn't get warm doesn't mean others won't either. It all depends on which way the windows face and if there is shade (which would take away the sunlight Gary is seeking to benefit from). It also depends on how well insulated the windows are as well. Some windows are single pane and others are double insulated to help keep the outside air temps from affecting the inside temps.

I do a lot of work installing anti-shoplifting equipment so I happen to spend a lot of time at the front of stores, usually made of glass. Sometimes the glass front makes that area of the building into a sauna. The rest of the building is nice and cool due to a/c, but the air around the windows is much, much warmer. Kind of like when you are driving and the sun is on your side of the vehicle shining down on your window, but not on the other side. It will be warmer by your window than it will be by the window on the other side of the car. Usually most people discover this simple concept when the are kids and go on long trips in the car. End up fighting with your bother or sister about who has to sit where! lol
I know in my house, the front room is in the sun the majority of the day. This is where I had my 58g tank set up and I was always dealing with temperature problems even with the a/c set at 77 and a ceiling fan running all day long. The back side of the house was cooler. I noticed even more as my desk sits in front of the front room window! I have insulated windows on my house, but not much help. I took the tank down and converted to a 75 gallon in the back room of the house and have no problems temperature wise even with running more metal halides.

In my opinion, putting a tank in front of a window that does not receive direct sun light (due to shade or not facing the sun) will not really get you the benefits you are seeking. The coral propogation companies have large tanks that are outdoors and open above so they get full sunlight when they want.

Again, just my 2 cents and not intended to sound funny to anyone either :-)

[GaryP]

Chris,

As I said in my previous post, I think that the light from the window will be a supplement, not a substitute for artificial light. I'm planning on using PC's unless I find a good deal on a 175 MH so I don't forsee a major additional heat problem. The PC's that I'm considering are the coralife that have built in cooling fans. Anyone have any alternative suggestions?

Gary

[captexas]

Gary -
I have the Coralife 96watt quad PC fixture on my fuge right now. I like it much better than the old Lights of America fixture I had from Home Depot. What dimensions are you looking at for the fuge? Depth will play a factor in how effective PCs will be and the size of course also affects how many you can fit over it. With the 30gallon long the depth isn't a problem, just the width to allow for the lights. If it is a fuge only with no pumps and such in it you might be alright but once you put a couple of baffles in there or a sumberged pump, you start to limit what can be done.

Hope that helps, if not just tell me and I'll shut up! LOL :-)

[GaryP]

Chris, since I'm going to retain my sump the fuge isn't going to have a lot in the way of baffles and no pumps. I'm planning on pumping to the fuge and gravity feeding back to the tank. That brings up my next question, what sort of flow rate through the fuge do I need to plan for?

Gary