My betta fish, whom I've had since February of this year, has been displaying the symptoms of swim bladder disease. He does like to hide in general, but recently I've noticed that he's been languidly floating at the bottom of the substrate without moving at all. This morning I saw him just floating almost completely vertically (again without any movement), looking up at the surface of the tank. He is currently in a 30g with a school of glowlights and cardinals. I've heard I should fast him for a few days before feeding him peas but is this feasible in a community tank setup? I'd really appreciate any advice on how I should proceed.