I have 7 cats - these are the cat litters I use They all use the same box, and I am a litter connoisseur. Karen M Smith FacebookTwitterEmail I never gave much thought to litter box filler when I had just one cat, two cats, or even three. When the clowder increased to five, it was time for a change for two reasons: First, my small house didn’t have room for half a dozen litter boxes, and second, regular clay-based litter no longer sufficed. With trepidation, I switched to “scoopable” litter and reduced the number of litter boxes to just one. Fast forward to today: