I have the omega 150 and the alpha 170 yes it does have an adjustment for the air mixture just that many people missed it on the instructions lol! or don't read them at all. The adjustment is the inlet to the venturi which is the white pvc part screwed into the intake of the pump. Turning it clockwise or counter clockwise will fine tune how much air is drawn into the pump. The performance of these skimmers are great and yes there is a big difference in build quality.
My 150 for the sps coral frag tank build
