If he shed 4 weeks ago he very well could be getting ready to again, even if you havent seen any signs yet. Or he could just be being a BP and for whatever reason just don't wanna. just had three really good weeks with feeding with everyone eating great, then last round nobody but the hatchlings and a few smaller ones ate. very frustrating to have to carry all those rats back down to the basement and put them away. If I didn't know better I would say they do it just to screw with our heads, lol.