I really like my 2R. I never need to adjust it. The pump does need to be cleaned periodically. It does take a few days to start producing. Adjust it to completely fill the first chamber with bubbles, keep the base of the collection cup about 1/8" below the water surface & most importantly, lose the return chamber sponge. This will clog & things will get wet. Micro bubbles should disappear within a couple of days also. That said, my 2R is equipted with the combo top skimmer/bubble trap. I don't know how much of a problems bubbles might be without the trap.
Ken