That's defiantly a photo of a fish suffering from intestinal parasites, a 5 -7 day course with something like Flubendazole should have cleared it up. If anyone needs this medication contact me for more details, you can also get a wormer from Plymouth Discus that would also do the trick.
Paul
If you only brought the fish on Friday, it's highly unlikely to have developed bloat in 4 days, the most common disease in newly introduced fish are white spot and fungus and the like.
It could well be an internal bacterial / parasitical problem; it's hard to say from the photo, but if you...
Hi Guys, Sorry to but in but:-
It's very difficult to say from the photo but it does not look like bloat to me! As I put my head on the block!
Are you sure that it's not a fungus or the start of white spot?
Paul