When we rehomed BiteyCat from the rescue he was a reliable litter tray user, but as soon as he got outdoor access he stopped using his tray completely.
For reasons I won't go into, he's confined to indoors most of the day at the moment and very unhappy about it. A couple of times he's climbed into the tray but not produced anything (I assumed because I was in the room at the time) and yesterday we came home to a puddle beside his tray (making a point?) Any suggestions for encouraging him to use it again? We are limited in scope for where we can move it (currently in a corner of the kitchen, part-screened by the laundry rack, where it has always been) but happy to try new litter, or other suggestions.