I was having an issue with my new(used) skimmer. The micro bubbles were leaking out past the injection tube. I was gonna just put a little in the leak. I did not want to make it solid(permanent), because I have to be able to disassemble for maintenance. I went to the hardware store today and just made new fittings/etc. Now the pump spits micro bubbles out from where the intake slide locks onto the pump. Maybe the rubber o-ring is worn out, I don't know. It is clean and fits properly, but still emits bubbles. The endless headache continues..........