I just rescued a coral beauty from a friend who got it from tank tear down. He said it was fine in the tank but it must have been in the bucket for a little too long. He is swimming with his face sticking out of the water. I put him in a new bucket with a mixture of existing water and some new saltwater. I also added an air stone and heater. Is there anything else I am missing to keep this guy alive. He is a beautiful fish and I would hate to see him die. Could the swimming up indicate a lack of oxygen?