return pump blowing air

[repair]

My pump will blow bubbles through it if the water level is close the the bulkhead in the sump. Sometimes you can see it pulling a small "vortex" and it lets some air in. If thats not the case I would think that its pulling air from a fitting somewhere.

Thats why you put a 90deg elbow on the intake so it can't happen.

 

[jsodwi]

still going I put the el on and tightened everything up. The air sound is coming from the pump though I can hear it pretty good. It is a little giant.

 

[rallysman]

is there a crack or a bad seal on the casing of the pump? I know the white part has to have some seals so maybe its coming from there.

 

[repair]

still going I put the el on and tightened everything up. The air sound is coming from the pump though I can hear it pretty good. It is a little giant.

I would move the pump below the waterline.

 

[jsodwi]

also I'm wondering, The overflow is a CPR 102 something 1200gph with 2 1" bulkheads I'm only running one 1" return it looks like rapids on the top of the water. Too much pressure coming out making the bubbles? would I diffuse the pressure somehow?

 

[TankBuster]

I had a similar problem with my reef tank, the bubbles from the protein skimmer and also the water flower over the partitions made a few bubbles in the sump, when they went through the pump, they were multiplied by a million. Are there a bunch of bubbles in the wet/dry tank before the pump? If so use foam that helps cut the bubbles or try raising the water level.