Is my gray tree frog sick? New frog owner!!

[tresmorn]

Hi - I joined this forum, because it is so hard to find information on how to care for frogs! In February, my mom caught one of her cats with a frog. He was still alive, I cleaned him up, and he has so far been doing well. I'm pretty sure he is a male (yellow inside of legs, throat patch, and ear drums now), and he was very much a baby when we found him. I have him in a 10 gallon tank with a screen top, some plastic plants, a rock cave, and two bowls (one for meal worms and one for water - he often sits in that to keep moist). The substrate is half coconut bark shredded. I keep this dry, because he gets it stuck all over him if its damp and the other half is a fake moss matt. He eats meal worms, because he had such a hard time catching and eating crickets. He couldn't see them or catch them and most of them died before he could eat them. I was misting him every day, but he really hated that. At this point, I'm not sure if he is too fat or not. He was eating 3 mealworms every other day (sometimes he'd eat two and leave one for the next night, etc.). This week, he's only eaten maybe two meal worms. He's sitting in his plant and looks alert. I picked him up yesterday (he's a wild frog so doesn't really like to be handled that much), and he's moist and he went to the bathroom (pee?) on me (so that seems to be working okay). No lesions or anything weird like that. I would really appreciate any advice anybody would have to offer. His name is Khan. I attaching 3 pictures: one of when I first got him, one that is just plain cool of him making himself white on a paper towel while I cleaned his tank, and one taken a few days ago. Thanks in advance! Beth