My boyfriend has what I consider to be an annoying habit of cleaning the our cat's food bowls out in the downstairs toilets. He empties the uneaten food into the toilet then washes them in the sink. I said that I didn't think he should do that because the food might build up in the U bends and block the toilet. He said how is cat food more likely to block the toilet than faeces and I don't know. Perhaps faeces is easier to break down in water than cat food but I don't know the answer. I'm hoping you experts might know!!!