I recently went through this with my cat. She's been on Innova weight management (dry) for the past year. She suddenly developed difficulty urinating, which resulted in a vet visit. They found tons of struvite crystals and an inflammed bladder.
She was put on Hills C/D (wet) for two weeks, then recommended Hills S/D (wet) after that. After reading the ingredients of S/D, I thought I could provide something with better ingredients.
After a little research, I found to look for foods that met the following criteria:
I've switched to Felidae chicken with rice and my cat gobbles it up, and no more crytals. Many UTI-friendly formulas tend to be chicken with rice.http://www.canidae.com/cats/chicken_...ce/canned.html
Additionally, using strictly wet food reduces the necessity for hydration. Very informative reading:http://www.blakkatz.com/dryfood.html