Looking at him he looks healthy, only you know his size and the size of the prey you gave him. You will be able to tell when he is looking for food...his head will be peaking out his hide or maybe a little bit grumpy.
I feed my 350 gram a 35-45 gram rat every 7-10 days. Sometimes he will eat on the 7th day, other times he will refuse and eat on the 10th.