Micro Bubbles Help - calgary

[slough shark]

I've had my 120 up and running for the past year or so and can't seem to rid my tank of Micro- bubbles. Im running a Mag 9 return and Im sure the return line isn't sucking air. After speaking with a fellow member, I think the culperate might be my skimmer. The skimmer dischrages into one compartment then water travels through 2 more compartments including a set of baffels before it hits the return pump but the bubbles still make it through. Then end up in the return pump then into my display.
A free adult Coris Wrasse to anyone who can tell me how to sort this out or come over and fix this problem.

I live in South Calgary.

best,
derek