If those are 12 x 12 tile squares, your guy looks like he should be taking down small rats in the 50-70 gram range about every 7 days. (that's just an estimate on my part, and not a recommendation).
If you can get a scale and weigh him, it will be helpful in figuring out what prey size to give him.
Offer food on a regular schedule, even during sheds. Some will eat, and some won't. Over time you'll get to know your BP and will be able to better determine when to offer and when not to.