OK, thanks all. I just realized that I had been adjusting my beckett incorrectly, for about 2 years now.

For some reason, I had it in my head that you opened up the air all the way, and the reduced it if your skimmate was too clear. With my air open all the way, I had dark skimmate, so I just left it open.

I recently bought a much more powerful pump (MAG 24) and read up on it again and realized that you are supposed to adjust the skimmer for many small bubbles. Having it wide open produces bigger bubbles, as I understand.

Hopefully things will work better now.