Black Cat Ranch has 6 adult cats, here's our system:
Sustainably Yours litter from PetFood Express
Clumps SUPER hard
Can be sifted with standard wire mesh sieve to get any small bits (like this one )
I scoop morning & night, and in between as needed. I do not dump unless there's really a lot of little bits in the litter that I can't sift out with the wire mess sifter. I clean the litterboxes monthly with hot boiling water and bleach.
I use "biodegradable" bags (box of 1000 bags) and they go in the trash but I keep thinking about digging a hole to create a pet waste digester in the backyard
In the last 30 years as an adult living on my own - I have gone through MANY many kinds of cat litter.
Clay is bad - mountain top removal and all that
Large pellets are a PITA and a mess, they fall apart
Never flush unless you have a septic system; else the risk is that organisms from cat poop end up leaving water treatment plants where they go to rivers and oceans and KILL OTTERS. You don't want to kill otters, right? Didn't think so.
Corn & Wheat have had variable results for me over the years - not clumping hard enough, powdery mess tracked everywhere, fermented smell that develops.