I stopped using cheap dry cat food just for that reason. Cheap food causes crystals, especially in male cats. They can be painful. That's why I switched to Wilderness. Best food on earth and cheaper than Royal Canin. Haven't had a problem with crystals since.

My vet told me that as cats get older, their kidneys have difficulty breaking down and filtering the urine. That's what happened in RB Murphy's case. She was 15 and her kidneys weren't able to filter out the urine.

Please keep us posted on your kitty's progress.