im thinking about building my 3ft long bp a cage. right now i have a 30l store bought tank for her and she doesnt have much room to move around. i want the new one to be about 4ftx2ftx2ft. i was going to build it out of plywood and have plexiglass on the front and screen on the top. it would open on the front. i have a few concerns. what should i use for the bottom so that i can use the heating pad? also how hard would it be to heat something that big and what would be the best way of doing so? any ideas or suggestions on the best way of doing it would be greatly appreciated