Hmm, not even sure if I have room for another hide box that he could fit in plus a big water dish... I was afraid someone would say that. He's full grown, but I can't imagine this tank not being big enough..

I don't see a reason to buy a UTH, as his basking spot in his hide box during the day is around 91. If everyone is saying that's a good temperature, I guess that's what I needed to know. It seems I will be seeing more of him now, on account of him being more active (higher temps) than before.