My Fish is of the Devil

I know it sounds harsh, but I think my fish is possessed. First off, this fish (a fresh water Red Tailed Shark, aptly named "Sharky") is over 4 years old. He has survived being left overnight in our brokedown Durango in the middle of winter, not being fed for a couple of weeks and a cup of milk being poured into his tank. The latest feat is surviving this last month. With the move and all we kind of forgot about him. Last night Katie was able to get him situated. He had been living in about a half gallon of water, his tank was green with mold and we hadn't fed him in a month. Katie did a great job of cleaning the tank and Sharky is just fine. I am just waiting for his head to start spinning around.