how do you stop noisy drians ???

[james]

my drian pipes are sucking way to much air and i cant get it to stop . i put small holes on top of the 90s that come out of the side of the tank ,down to the sump. i put some air tubing in them .thinking that the air would have somewhere to escape . that is what one person told me to do . it did not work at all that just slowed the drains right down and the pump would drian the sump ..... if any body has any ideas that i could try it would help . this tank is right beside my bed so i dont think i will be doing to much sleeping if i can't get it right . please help if you can. sorry no pics . i am trying to borrow a cam. to take a few. i was just looking and the noise is coming from just one side. could it be the tank is unlevel . would that cause this problem.