I was having the same issue. I bought a repti fogger and the zoo med hydro therm. I'm using a 60watt ceramic heat emitter to keep the temperture up and the repti fogger to keep the humidity up. I also have a 13watt exo terra natural light on a 12 hr on and off cycle. I spray the tank every morning but It still drys up by the afternoon. The fogger keep the humidity up but the ground gets dry. Any suggestions?

I keep the top covered with tin foil on one half side and a towel on the other side.