I ve heard that a number of things can cause swim bladder issues, if the water parameteres were different enough that may have caused it. I would agree don't feed him for a few days then try skinned peas and give him a few weeks. Hope it works out..
here's an update after a little more than a week of treatment, does he look better?
[video=youtube_share;Oh4_ca2fsbs]http://youtu.be/Oh4_ca2fsbs[/video]