Overflow boxes

[nyreefer]

I'm going to be setting up a 20 gallon fuge for my 55 and need an overflow box. I have read that Lifereef and Amiracle are good to use but I'm having a hard time finding them. Lifereefs are currently sold out and I can't find Amiracles online. I've seen lots of CPRs but do not want that brand. Any help would be appreciated.

 

[nyreefer]

Ok I found some overflow boxes and I just need to decide between Amiracle and Marineland's TidePool SOS. Has anyone had a bad experience with either of these? Thanks...

 

[tony detroit]

I had a cpr on my old tank, worked like a charm.

 

[cyslyde]

kinda on the same subject... I am going to attempt to make my own overflow.. right now i use a powerhead to get the water down, and back... I was inspecting a CPR overflow for a 60 at teh LFS today, and was wondering what the tube at teh top of teh siphon was for?

 

[broomer5]

NYReefer
Are you planning ( or already have ) a sump under the 55 gallon display tank ?
The reason I ask ..... most hang on external overflows require a certain amount of flow through them, call it a minimum flow, to insure that air bubbles do not become entrapped in the upper curve of the U tube. If you don't have enough flow through the U tube, small air bubbles WILL accumulate in the upper curve. If this happens, and this air pocket grows large enough in there, it will cause the U tube siphon to break, the display tank will overflow and you'll empty your refugim ... and may damage the return pump.
If you have enough flow to keep these air bubbles moving through the U tube ..... then you'll be fine.
Most folks keep the flowrate through their refugiums pretty low.
Many folks will use a sump AND a refugium to overcome this U tube overflow minimum flow requirement.
Lots of ways to use a sump & fuge combination.

 

[nyreefer]

Broomer,
I had just planned on a fuge but can add a DIY sump if that is the case. I understand the concept but I really think it's one of those things where you're not going to know until you really try it. I am a bit confused on how to keep high flow out of tank and back to tank but low flow in fuge. I planned to install baffles in the 20gal fuge and go from there. Thanks for the help.