Thinking outside the Cat Box

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If you clean the litter box daily, you might only need to change clumping litter every two to three weeks. If you notice an odor or if much of the litter is wet or clumped, it's time for a change.
Scrub the box every time you change the litter. Use mild dish detergent to clean it, as products with ammonia or citrus oils can turn a cat off, and some cleaning products are toxic to cats.

Liner notes
Box liners are strictly a convenience for the owner; supposedly, the liner can be gathered together and tied just like a garbage bag, but the truth is that most cats shred it to bits while scratching in the box. However, it might work if your cat doesn't work too hard to bury his waste.

Depth of litter
Some people think that the more litter they put in the box, the less often they'll have to clean it, but that's a mistake. Most cats won't use litter that's more than about two inches deep. In fact, some long-haired cats actually prefer less litter and a smooth, slick surface, such as the bottom of the litter box. Adding extra litter isn't a a substitute for scooping and scrubbing.