I was cleaning him out and put him in the sink a normal and he was fine... Then I put him in his tank and he started floating like dying so I was like ok ill try Coolin the water down maybe it's too hot for him even though it was only just over the line o thermometer so I filled a jug up with cold water. But he died.. I feel so bad I found him a nuisance so I'm scared subconsciously I killed him : maybe I didn't try to save him but what more could I do. Also how long do they live?? I had him for like 2 -3 months. My friends died within a week when we got them. Maybe I'm a fish killer Ill never forgive myself