I just got a new DT two days ago and I found him floating around on the bottom of the tank today before I went to work.He never ate while he was here and it looked like he did not eat much at petco either.He also had a bump on his one side so maybe he already had something.I personally think he messed up his spin or broke his neck doing something he was tryiing to jam himself against th ewall and the filter he did not fit and he got stuck earlier I saved him but he almost jumped out of the tank so I put the lid to the cup he came in over it so he did not jump out.He was affraid to back away from the filter and he only stayed in the one corrner.So I am pretty sure he killed himself doing something he was a really scared fish he was affraid of everything, he was super freaked out in a 2.5 gal so he probably never would have been able to be upgraded to a 5 gal.Poor pretty guy never got a name.