1.) Is your BP a baby/hatchling? A 40qt might be a bit large for him/her. Make sure to put a hide in both the cool side and warm side of the cage and maybe some balled up newspaper so it's a little more cluttered in the cage.Originally Posted by Stings
2.) The temp on the thermostat may have to be higher than the desired temp inside the cage. Keep tweeking the thermostat temp until you get the desired side on the warm side (92-94) More holes in the cool side will allow for room air to circulate into the tub to get the desired temp gradient.
3.) From what I've read/heard, your snake will not cook itself. If you turn up your thermostat to get the desired temps, your snake will use the warm and the cool spots to thermoregulate properly. Just make sure there are multiple secure spots in your cage in different temps so that he can move from warm to cool independently.