No, not what you're thinking! We changed Harry's litter from Catsan to Felipure clumping and he likes it too much - he keeps coming in from the garden to use his tray!
The problem is when he wees he goes right against the edge of the tray and it welds to the side and is a bugger to scrape off. Is it better to wait until it dries and then scrape off and remove the clump? I've got loads of litter in the tray so it's not sticking to the bottom, just the side.
I wouldn't have thought a little cat could produce so much wee!