Bowls are washed as needed. He eats dry food, and a spoonful of yogurt (vet approved) once a week (keeps the cat breath at bay). He has 1 food bowl and 2 water bowls- 1 by the food, and the other at the other end of the house. Somehow the water bowls need to be washed at least twice a day because there's always food crumbs in them?