I also line the hot side with damp sphagnum moss - that way there is about an inch wide and deep pile along the length of the UTH. It dries out about daily due to that and the CHE on that side. The sponge is on a plastic plate on the cool side just so the bedding does not mildew/mold, and this sponge is way too big for him to eat just in case he gets confused by the warm sponge lol.
I have a T11, so the right side has almost no bedding since that is where the UTH is and my snoot does not burrow at all so the moss is directly on the plastic bottom. When in shed, I shove some of the moss in the hide with him as well.