My BP has a pretty big tank, about 3ft by 1 ft (not sure gallon wise but I think 40G?). Anyway, I have a hard time keeping the temperature up, I have a UTH under on the right side and a small UTH on the back side in the middle, I also lined 3 sides of the tank with aluminum foil. But it's dry and getting very cold here in CO so I'm not sure if there's another way to keep the temp up that I don't know of, oh and I also have a towel on top to keep the humidity up which is doing the trick. Thanks!