slick:
I'll tell you a story that happened to me and you can decide if you want to attempt same; I used to have some Tin Foil barbs, large ones, and one developed a problem with his swim bladder, much as your fish has. What I did, seeing as I did not want him to die but figured whatever I did MIGHT allow a natural healing, is that I built a 'narrow channeled' holding tank from plexiglas. My fish was probably 4 inches long. The holding tank about 18" by 8" by 3". The narrowness does not allow the fish to flip and this gave the fish a chance to recover (which btw, he did, though he was never the same re swimming, but he lived for a goodly while thereafter). Of course I had to monitor the 'aquarium' water quality and added air. The trick is to make the aquarium narrow enough so he can't turnover. Actually, now that I remember, I put the holding tank inside my 50 gallon and drilled small holes in the sides and bottom so there was an exchange of his water with that of the 50 gallon, which had the rest of my tropicals. So, not a huge expense (plexiglas and silicone, separate airstone/pump) but it might give your fish a chance like it did mine.
Anyway, maybe this will help.
Michael