HOB overflow help

I'm using an HOB overflow and the plastic u section of it has a large air pocket in it and I think it is restricting flow. How do I remove this air pocket?

 

Insert some airline and suck it out.

 

Alright so just stick the airline tube into the air pocket and suck it like a straw? Can I do this without stoping the overflow?

 

If you can get the tube in there with out having to stop it, yes. make sure you pay attention to the bubble if you're gonna have a salty drink...lol

 

Alright another concern I have is I lose about an inch of water in my sump every day. Does evaporation occur this fast, or is it something else? I have a 75 gallon tank with a 20 gallon sump.

 

an inch a day is fairly normal. Just check for salt creap or wet spots on the floor. I probably loose about that much in my 55 with a 20 long sump per day.