Thanks everybody. Ironically, right after I posted this I dangled a pinky meant for my snake into his cage saying "you won't eat this will you, cause you're stubborn" and he jumped and ate it... His temps aren't quite at 85, but where we live his tank gets to about 80 during the day, so adding any extra heat source makes it WAY too hot. I think he might just be a bit of a picky eater.