I'm pretty new (got mine in October) to this, but I have the same type setup except I use Aspen. The only way I've been able to keep up the humidity is with a damp hide. You can find directions on here, but it's damp Spaghum Moss in a container such as a margarine (I got a cave for Xmas) tub. She goes in there when she wants some wetness, and it keeps the whole tank at around 60%