If you want to get him switched over to rats, try a live pup. One that still has its eyes closed, it can't hurt him. Then you can just leave it in his tank, in front of a hide, or under heat lamp/over heat pad. If he is hungry, and you leave him alone, I bet that rat dissapears. We had a picky eater baby, and we put a pup in front of her hide, covered tank, and started eating diner and watching tv. An hour or so later we heard, eeeeeeee. Took a peek, and rat pup drug in hide, coiled by snake. She hasn't looked back since. Imo, would try to get him as rats as soon as possible.