I have my adult male panthers basking spot highest temp at 90F, usually closer to 85F, with room ambient around 69-70F this time of year. This appears to be enough, since they mostly only got the hot spot in the early morning and hang out elsewhere most of the rest of theday. Gradient is the key - make sure they can move away from the heat. For females I have the basking spot a little lower temp, 80-85F. Youngsters even lower.