How tall is the tank? I have a 40 gal for my son's snake. It's about 18" tall. I had to insulate the bottom and every side but the front with Reflectix insulation. Using a Herpstat II we control the 75w infrared and the UTH. I have the top screen covered with Reflectix and I use a damp towel to control humidity.
For a glass tank its perfect. You may want to try a stronger bulb in a 50 gal. or try to insulate the cage. I have photos to demo some if this if you need to see it.