I use misc. types here, for clay I like Cat's Pride, and for clumping either Wal-Mart's brand, Arm & Hammer usually anything except Cat's Pride brand of clumping. There's nothing like having the dust fly into your mouth, and nose from that stuff. It's like scooping baby powder...yuck! I'm not a fan of Tidy Cat either...any litter that comes out of the bag grey, ends up black in no time. Nothing like scooping mud.