To help reduce bubbles, I added a deflector to the basic cerges design.
Part of the reason bubbles escape the reactor is the incoming stream is directed straight down. By forcing it sideways, there is less chance of the bubbles reaching the bottom. It also creates a visible rotation in the reactor that might help it work better. I don't have hard data, but this does restrict flow slightly.
Pretty simple to make, just takes a tee and a street elbow.
Once the two pieces are glued together, use a Dremel to remove most of them
. The tee piece needs the back half cut off so it can saddle your existing return pipe. The street elbow gets cut to shape and to fit your housing. Once everything is fit, just glue it right onto your existing pipe.
I still get a few bubbles, but it is greatly reduced. Hope this helps.