oh yeah, it's normal. he's being shy and thinks he's hiding. you just have to wait a while until he gets acclimated and de-pussifies. it's a very common rhom thing. he'll eventually find a place in the bottom third he likes and settle in once he feels safe. total waiting game with new rhoms. don't worry. as soon as you turn the lights out at night he's cruising around and exploring and getting the lay of the land. my young rhom recently came around and became more brave and active in his tank, but he still heads right to the top and attempts to hide if he gets spooked. you could probably really throw in a lot of plants and wood so he feels super hidden and he'd probably come back down. of course then you can't see them.