pvc overflow - losing siphon

[Danger_Chicken]

Thanks, I thought that's what you meant but wasn't sure. I think 3 of my tanks have that type of powerhead all the other have the Hydor type.

For tonight I stuck some clear hose to see what happens.

 

[mjohns]

Least u can see the air buildup etc..

Not really the design of overflow i would have used but it hope it works out for you, let me know though please.

 

[Pharaoh]

I have found these overflows to be very inconsistent. I made one almost identical to your and it blows the big one. I would suggest to either try the powerhead idea or get an aqualifter.

As far as the position of the check valve. This suggestion might have been made base on the idea that there might be a spot on the inside that is trapping air. Moving it to one of the corners would be a higher point than in the middle. But, if your pulle water out of the U-tube via sution, it should matter too much.

 

[Danger_Chicken]

soo far the hose is working

 

[Pharaoh]

Great to hear. Sounds like it was the check valve or a small leak in a PVC connection.

 

[coolkeith]

I've had nothing but bad luck with Check valves also. One thing that helps is that I use duel inlets so that air doesn't get sucked into the overflow as easily. With just one inlet the suction is twice as strong and enough to pull air into the overflow, with duel inlets the suction is cut in half. Here's a pic of one of my overflows-