I have a Coralife super skimmer and it seem like it is hard to adjust the bubbles to the right height. I can set it where the bubbles barely start going up the tube and I get very little foam, or I set the bubble going @ a 1/4 to 1/2 up the tube and get @ a collection cup 1/2 in 8 hours. Is either of these setting right or is there somethine I need to be doing?