Air bubbles from powerhead

[Anonymous]

I have a CPR overflow box. In order to keep a constant flow; and to re-start the overflow in case of a power outage, I use a power head connected to the air tube.

The problem is, it draws air from the tube on top of the box and shoots it into my water. I attached a hose to the power head and it runs around my VHO lights and into the overflow box.

This is very unsightly and I was wondering if anyone else has this problem and what to do about it.

Thank you

 

[Anonymous]

Thanks for your advice. I will test your idea this weekend.

Thanks again.

 

[Anonymous]

I had the same problem. I put the powerhead in the overflow box the way roo suggested and that worked except it flooded the sump with bubbles, some of which made their way back to the tank.
I realized that if the flow was fast enough through the overflow that whatever air got sucked in would be "blown through" without having a suction on the fitting at the top. I opened the return pump from the sump wide open, used a short piece of soft airline (the surgical tubing kind) to suck the air out by mouth the first time, folded a kink in the tubing and put a clamp on it. Works fine now without a powerhead sucking the air out. When bubbles get sucked in they get blown through. A little bit of air is always trapped in the top but not enough to interfere with the operation. If your return pump is not strong enough to produce the flow volume through the overflow, the air will build up and eventually stop the siphon. Your return pump from the siphon is the throttle for the whole process. If it can't keep the bubbles pushed out, you need a stronger pump.

 

[Anonymous]

I just bought one recently and I'm having the same problem. I've email CPR and a technician wrote me back. He said to put my power head in the sump. But the problem that I have is I already have too much bubble in my sump. I'm trying to get rid of the bubble there. So I'm thinking of returning it. Maybee the power head in the sump would work for you.
Richard.

 

[Anonymous]

Had the same problem but saw a way to fix it on one of these boards. Put the powerhead in the back of the overflow where the prefilter is. I used a aquaclear 402, did some minor cutting and drilling(put the airline up through the bottom of the powerhead so it got a lot of suction) added a 2-3" piece of pvc to the bottom of the overflow(so the water level in the overflow was about 2-3" deep) It's hard to explain but you just drop the pvc pipe over the drain in the bottom of the prefilter(I added some silicone to seal it good)then put the prefilter sponge over that. The idea is to have enough water in the back of the overflow so if the power does go out there will be about 2-3" of water that won't drain out of the "box" so when the pump starts back up it will have enough water to start the siphon again. Mine has worked flawlessly!
I have all cpr equipment because I thought they were one of the best but now I'm not so sure. I have a cpr sr-6 skimmer and that thing is ALWAYS kicking fine air bubbles back into the tank. I've tried everything and talked to everyone but nobody can help. Next time I'll go for the ets. reefdevil!!