I actually have a pretty similar question. I just got a baby biOrb
and new betta at home! I was pretty pleased with my library fish (who the students have named Mr. Bojangles) and my husband decided to humor my new obsession for my birthday.
This tank is about 3.75-4 gal and also comes with an air pump that sends a lovely column of bubbles to the surface. But the water looks like it's boiling when the bubbles break, it moves so much. I've kinked the air hose so that only a few bubbles come out every 5-10 seconds or so, but I'm curious if anyone has any experience with this and thinks I should leave it going full-bore, keep it kinked so a minimum of bubbles get through, or turn it off entirely? - I've got lots of extra hose to work with, so I can always cut off the kinked end later.
The baby biOrb has its filter in the bottom of the tank, under the bubble column, so I'm wondering if perhaps the air flow helps with filtration, or if it just aerates the water.