I use aspen for my rats NOT for my snakes. Paper towels are okay but my snakes bunch them up too much. I like pieces of carpet best. I wash them after every soiling in color safe bleach so no bacteria buildup like some claim is the issue with carpet. Wood chips or dirt of any kind is too dusty/dirty and gets into/onto everything inside and outside of the enclosure. BP enclosures are small compared to the animal and in my opinion, after one elimination more than a spot clean is in order. Snake doodoo stinks and I want it 100% gone as soon as it lands!