Last night I fed the fish, but instead of dropping the food in the tank I kept it in my hand and the fish actually swam right up to the top of the tank and grabbed it out of my hand, it kind of bit me aswell. We moved the tank to a very dark area for a long period of time, when we put him there he was a very dark blue colour , but when we moved it back into the light we noticed that it went back to a redish brown colour. We observed this a few times in the morning when we put on the light of the room that the tank was in. We think its colour ultimately depends on the light it is exposed to, therefore when we expose our fish to minimum light its colour goes to a red-brown, but when it recieves more light it changes to a green-blue.