I use carpet pieces. The cheap non fuzzy kind at lowes on the roll. I also use sterilite tubs. The urine gets the carpet a little wet but most of it drains through and settles into the depressions on the bottom of the tub keeping snakey dry. When I see a steamy tub, I know there is a mess to clean. I pull out the used carpet and wipe the tub with vinegar. The soiled carpet section goes into a 5 gallon bucket (with lid) and replaced with a new piece. When the bucket gets full, into the washing machine it goes with fabric safe bleach. Cheap, easy, and clean. I tried aspen and it made a mess on the floor in front of the rack. Paper towels are okay but the snakes mush them up into the corner. Newspaper turns white or light bellies gray. Carpet is king.