cxg31s I don't want to discourage you in your search for the perfect spot for your litter box, but the bathtub has some potential problems I think. If you use a clumping litter and the granules should go down the drain I am afraid that the litter might clump in the pipes when water is run and will clog your pipes. Maybe somehow seal off the drain so that doesn't happen. Also, I would think your dog could still get in the bathtub because my dogs had no trouble jumping in the tub when it was their bath time.