You can adjust the height of the skimmer cup. There is a small black screw that holds the cup at a particular height. You can loosen the screw and raise the cup a bit then re-tighten. You kinda have to play with it. I have this skimmer but maybe an older model, there is no bubble adjustment knob (on mine at least). You make the adjustments by moving the skimmer cup up and down. Up=a more dry skimmate and down= a more wet. You can watch the height of the water like in relation to the cup and that might help a bit. Careful if you put it down too low you will just wet skim and fill the cup in hours not days causing an overflow onto your floor. Trust me, if you make adjustments make sure you check on it after a hour or two, don't leave for the day!!!
Oh and make sure the O-ring is snug. It is not a bad skimmer but a bit of a pain to dail in. Mine put out a ton of micro bubbles. I put a regular straw in the water return to make them stop (mostly). But looking that the link your is a 90 deg and mine has a T with the top open to put a straw. I hope that means that the 90 deg solved the issue. Good luck!!