Ive got mine in a 5 gal with 5 or so inches of sand. I've also got a 2.5 with around 6 inches of 1:4 mix of sand and excavator clay drying which I was going to use for him. Since depth of substrate is more important to these guys then square footage ground space.
I heat his enclosure from about with a 50 W IR bulb all day and night to keep it 27-32 degrees C