I got this fish a few days ago. He had been in the store for a few weeks at least. I didn't see anything wrong with him at first other than his tail fin was nipped off a bit and he didn't seem to have a lot of energy. Well, about a day after having him home and floating him in a 10 gallon as I don't have a heater for my qt tank, I noticed that his sides appeared to have this black, splotchy look to them. I'm just wondering if it's normal or not. He eats and swims around in his cup, but sometimes it's hard to tell if his fins are clamping or not. Sometimes he just rests and his tail fin just comes together. Please take a look. PS, that's not how much water I'm actually keeping him in.
http://www.youtube.com/watch?v=frjQzUfy_rs