Air bubbles in overflow.

[mwheeler]

What is a good cheap pump to hook up to my overflow to keep the air bubbles out of it? Something i can put into my sump and run a "air line" size hose up to my overflow. It has the hose connection on the top where the air gathers.

[Rick]

Air shouldn't be gathering there. Any air up there should flush out shortly after it starts draining. I would check that "connection" on top for leaks. Personally I prefer an overflow tube that doesn't have it. It requires sticking a piece of tubing up the overflow to suck the air out but only should need to be done once.

[mwheeler]

I don't have this brand of overflow but it is the exact same setup. I am thinking about getting this pump though.

 

http://www.fosterandsmithaquatics.com/product/prod_display.cfm?pcatid=3642

[Rick]

The only reason for the pump is to get the syphon started. (which can be accomplished without the pump) Once the syphon is started and it is draining the air will flush out of the tube as long as there isn't a leak in the top. Unfortunately (as it appears is the case on yours) this adds a spot for potential failure. As long as both ends of the tube stay submerged and it is sealed then you can even turn off the pump and leave it that way for days (until the evaporation drops below an end) without needing to start the syphon again.

[mwheeler]

I might just get some silicone and put that around where the tub comes out the top of my overflow to see if that makes the air bubble go away. It would be cheaper and easier.

[Rick]

I might just get some silicone and put that around where the tub comes out the top of my overflow to see if that makes the air bubble go away. It would be cheaper and easier.

 

That's what I would do. Also be sure the tube is in correctly. I've seen them installed backwards where it would block water flow on one side. (Usually this causes the tank to overflow though)