Do you have a cover on the tank? The reason I ask is that I had a moray like that one years ago in a 200 gallon tank. One day he decided that wasn't big enough for him and he slithered up and over the side. We didn't find him for about a week. They aren't like a fish that will pretty much die where they land. He had crawled about 20 feet and died underneath the entertainment center. You said you were attached to him, so I thought I would mention that they do find their way out of the tank. In fact, they are pretty good at getting out. I would put a glass cover on the tank, since it can probably push a light screen top up and slide out underneath it.