I have a Top FinPower Head with the Air Regulator. My question is when I first put it on, there were a lot of bubbles forming. As time has gone by, the first inch or so of the air tubing has water in it. Is this nomal (I am not seeing many bubbles now)?
The ones I have experience with are Maxi-jets. They have a little plastic sphere on the end with two halves that could rotate. That adjusted the amount of air. If I disassembled it completely there was a little cotton pellet in there. Yours could also be blocked at the junction to the powerhead. It really looks like its air supply is getting choked off.
BTW. I took it out and noticed the end does turn to allow more or less air. Wasn't the issue, I think when I turned it off once during a water change water got in the air tube. Cleaned it out and has worked perfectly since. Just wanted to give thanks for the help.