Call the vet where you had him neutered and tell them what's going on. He may have a bladder infection and need antibiotics. If you take him to the shelter b/c he isn't using the litter box, his chances of getting a new home are pretty slim. Make sure he has access to a very clean litter box all the time. If your home is big enough, you should put down more than one for him so he won't have to hunt for one if he needs it. Make sure you keep all your clothes, towels, etc. picked up and put in a hamper with a lid. Clean up any "spray" spots with an oxy-based cleaner to get rid of the scent. Chances of your cat playing with a dying fish are very slim. Cats like to watch fish in an aquarium and if you leave the lid off, they might stick a paw in, but to be confronted with a panicked, dying fish flopping around noisily in a sink would weird just about any cat out.

Izadore (Izzie) answered on 5/1/12. Helpful? / 1