The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.
This is a bit different, but my fuge that returns to my sump used to throw many bubbles, i just extended the return hose (don't know if that's possible for you) and now the water returns just slightly under the water level of the sump......bubbles are now gone!