I'm really not sure. I fed the tank at 3P and he came out to eat, was swimming around and looked fine. Went to a party. Came home at 1030P and he was on the bottom, dead. It was really strange. He was so cute, too.
no one else is showing any signs of anything. The only other fish in there are a Firefish, a very small clown and the dwarf angel. I have seen the angel chase some new fish around at times when he was in the 55g, but have never seen him chase any fish in the current tank. And I've never seen the angel hurt any fish ever. Everyone seemed to be Getting along and doing well. Very strange.