My soon to be 16 year old FIV positive kitty was just diagnosed with kidney disease. The doctor recommended Royal Canin kidney diet can food or Tiki soft cat food. I bought both. My cat has been eating some and is already showing improvement, playing like crazy, which is wonderful. Only problem he is starting to not like either brand and is begging me to feed him something else. He is just not getting enough food and is already underweight. Does anyone know if there's other brands that are safe for kidney disease?