Switching litter in an automatic box? Blending two litters is what a sifter handles worst. Here is how I switch across three cats without jams or odor.
Crystal, Pine and Tofu Litter in an Automatic Box
Every page says use clay and stops there. If you cannot, here is how each alternative actually fails in a sifting box, and the narrow cases that work.
Best Litter for an Automatic Litter Box (and Why)
Every page says use clumping clay. Almost none says why. The machine is a sieve, and once you understand what a sieve needs, every litter decision follows.