Quote Originally Posted by CntrlF8
It's a Reptile Basics closed rack. Only one end is open.
So my first thoughts are wrong since you have a closed rack. If memory serves that rack has back heat? How long are the tubs? If you are using the 41QT then it just might not be enough to heat all the way to the front (especially if the room is kept cool).

Since you aren't keen on Vaugn's idea to heat the room you could add some flexwatt to the front of the rack to add more heat?