help setting up refugium

[MikePetisco]

ok i have a 55G reef tank, i also have a 20g i want to use as a refugium. i am building a custom cabinit to fit both tanks. The refugium will be above the reef tank. My question is how do i know what the flow rate will be? I was thinking on making a Overflow box from the DYI section. then having either a powerhead send ing water back up. If the power head is a good option which one will do the job.

or i have another option i have 2 ehiem filters on the 55G a eheim 2217 & a eheim pro. II 2026. Can i use one of the returns to feed the water back to the refugium?

TIA

 

[Mac1]

You ideally want to have the water from the refugium return to the main tank via gravity, and I would recommend trying to get a drilled tank instead of using a HOB overflow. Fewer problems, easier to work with, worlds safer... and if you're in the "Setup" stages now anyway, it won't be that big of a deal to change.

The Flow rate people recommend keeping things kinda slow... hard to quatify but based on your tank size I would say maybe 100-300 GPH. So depending on how far and high you're pumping your water, you may need a more powerful pump than what the Eheim's can do. You can create a really low-flow refugium, which will work just fine, but I find I like a decent amount of water movement in there... helps stir them bugs up! Also, as your refugium fills up with algae and other things, the flow through the tank will become rather diffuse. I know when mine gets chocked full of that Chetomorpha, there seems like hardly any water movement.

- Mac

 

[Mac1]

The size of the hole to get drilled depends on the size bulkhead you are going to get. I'd recommend at least a 1" Bulkhead for drains (even if it's going to be lo flow), and would second what Kipreefer said. Get it drilled twice in case of problems. If you can find a LFS that will do the drilling for you, than they can size it for the bulkheads. Otherwise you might want to talk to them about ordering a custom tank (AGA will drill your tank anywhere you want for a reasonable fee... just takes some time to get it delivered).
I forget what the sizes are to use, check in the DIY section if you're going to drill the tank yourself. It's prolly best to find the bulkheads you want to use (and purchase them), and then drill the holes (so that there's no "Whoops" after you make your holes).

- Mac

 

[sillingw]

I agree with kipreefer, Mine is a 30 gallon refugium, with two one inch outputs that gravity feed back into the system. On is drilled slightly higher than the other - my refugium grows quite a bit of algae and I was concerned that the primary outlet may get blocked (this has never happened) so the second one was ther just in case. - I pump around 150 gallons per hour thru mine.

 

[MikePetisco]

ok ill get the 20g drilled thats no problem.
The question is how big of a hole should i get it drilled.

 

[kipreefer]

i like getting my refugium drilled in two places. Just so if my macro algaes clog one hole i odnt have water all over my floor. OR just drill it alot bigger tehn what you think you will need. Say 1-2 inches or so.