Refugium flow - any help

[broomer5]

Tank: 75 gallon
Just finished replumbing my sump, overflow, manifold/multiple spraybars and under tank refugium.
Refugium is an 18 gallon Rubbermaid Roughneck, with twin sidemounted 1 inch bulkheads, piped spillways into the sump. Redundant I know - and certainly is far greater than I'd ever intend to run through the refugium, but they were the only bulkheads I had on hand.
I would like to hear advice from any refugium users regarding what they feel is an ideal water flowrate through their refugiums. I can run water into the refugium either from my display tank drains, or from my return pump, and have installed a valve to regulate flow either way.
I have a way to measure this flow as I adjust the valve as well.
Nitrate export is my main concern, but will have a DSB and some live rock included.
Any help and experience you'd like to share would be most helpful.

 

[jamie1010]

ok just so u know where im coming from. i dont even have a tank, and this is my opinion and not fact. flow rate doesnt matter unless u are depriving the algae(im assuming this is what u are using to export nitrate)of nitrogen, or you are damaging the algae from too high of flow rate. have u ever seen rocks in a stream they are covered in algae, not the same kind, but they are still more than likely taking nutrients in the same way marine algae does. if you put that kind of flow rate in a refugium more than likely it would destroy your algae and it would be everywhere,and i doubt if youd have a dsb anymore. as far as the deep sand bed goes most of the flow would bypass that anyways so i cant see how it would bother that either.the only real reason i can see for having a low flow rate would be so all your creatures in there stay in there. and just to start trouble i think gph is too misleading 100 gallons flowing through a 10 gallon tank is much faster than 100 gallons flowing through a 100 gallon tank so when people say 50 gallons per hour for a refugium is that for a 10 or 100 gallon refugium. mabye it should be argued like watts per gallon.hehe. hope that helps you make a decision but remember im not basing it on any fact just my theory.

 

[mr . salty]

Your best bet is to make it as slow as possible.I have my 10 gallon fuge running at about 70gph.I say the slower the better.

 

[lordofthereef]

you should try to get the flow rate to one time the tank volume through the refugium per hour. like mr.salty said, the slower the better.