My 7 yr old cocker spaniel is having surgery to remove a bladder stone that is too big to dissolve naturally. The vet want's me to change her diet to Royal Canin S.O., but everything I'm reading says she needs to be on a grain-free low protein diet for prevention. I read the ingredients on the Royal Canin & it's chock full of wheat, wheat gluten & corn. When I try searching the web for grain free low protein diets I get so many results on just grain free or low-protein and I am overwhelmed. Figured I'd post here to see if someone can help me. She was previously eating Solid Gold's Holistique Blendz, which is low-protein, but it does have grains (not wheat tho). The grain-free food that Solid Gold offers is high-protein (30%, vs the 18% she's been eating) HELP?!