I think you may be underestimating how large a meal he can eat. I have some 00 rosies and they are eating hopper mice with no problem. Even if he is on the small side, he should be able to handle that. Can you post a picture of him with something next to him to get an idea of his size? I would feed him twice a week and with larger meals and get some good weight on him before he goes into brumation the next time. It may be that you have not been feeding him enough inbetween periods of brumation. Hope this helps some.