Give me the good, bad and ugly of CPR overflows

[fishfreek]

Ok, I am looking for an overflow for my 80 gal tank. The only overflows I can find on the online stores are CPR brand. If anyone has had experience with these overflows please post a response so I can make an educated decision about buying one. I am looking for 1100gph flow at the most and 800gph flow minimum.

[Bob Ashcraft]

I'm not sure who makes this (could be CPR) but this should work.

http://www.aquaticeco.com/aquatic1v1...&srcquantity=1


I use a Tidepool SOS, and am happy with it. You'll need 2 of them since they're rated at 600 gph.

http://www.aquaticeco.com/aquatic1v1...&srcquantity=1

[fishfreek]

Ya the first one you posted is the CPR.

From what I have heard they acutally "require" a PH to keep the syphon going if the pump stops. I know the "U" or "J" tube style overflows will NOT lose the syphon if a power failure occurs.

Personally I think that is a poor design if this is the case with the CPR's.

[Bob Ashcraft]

I'm not familiar with the CPR, but the tidepools do not reqiure a PH to keep the siphon if the main pump quits. It does however use a powerhead to keep air bubbles from accumulating in the tube, and eventually breaking the siphon.

[fishfreek]

LifeReef

I am looking at this overflow now. I will need the dual unit and I expect I will modify the overflow a littlebit so I can remove the sponge's on the back and maybe add a short lengh of pvc to the down flow ports to cut down on noise.

[Anemoneman]

I use two overflows on my 75. I'm pumping about 600 gph. One won't keep up. You want high flow through your siphons, that's what keeps them from getting airlocked. I use simple U tubes. Cheap and effective. When I clean one, I throttle the pump back and use the other one.

FYI

Mark

[reefrunner69]

Just a thought, but instead of two overflows, couldn't you simply use two U tubes or J tubes in one overflow. I used to do it all the time.