In my limited opinion, needs to be hotter. My indoor guy has a 900 sq. foot "enclosure" and his main space (also stepped) has been(at it's highest powered) 250 x 2, although now it is 160 mega + 250. In both scenarios he spent a good amount of time at the top step (20" distance) before basking at 24", which is why I am considering adding a 250, making it a 250x2 + 160 mega. I don't worry about (nor even know!) how hot it is precisely, as much as I let him tell me what he needs.