I keep mine around 78 with a warm spot of 82 (they never use it), but I shut off all heat at night, and the room gets down to 72 this time of year.
I also provide a fairly large water bowl, a hide filled with slightly dampened sphagnum moss, and paper towel for a substrate.

Mine feed on F/T pink rats once a week, and seem to do okay with the setup they are in.
hope that helps.