Some of the first commercially available cat litters were non-clumping cat litter, being very similar to what a cat is used to from the outdoors (sand, soil). Non-clumping cat litter needs to be fully replaced at least 1-2 a week as the urine does not clump and cannot be removed and therefore the litter box will get soiled quicker as the urine remains in the box. We offer both clay and biodegradable non-clumping cat litters.