Good for him staying away from the dry
smart kitty
The prescription diets really are not formulated for cats biological need for protein. Yes they are low in phos & protein but also taste and nutrition.
Try
Wellness grain free Turkey,
Wellness grain free Chicken and
Wellness grain free Beef & Chicken those are the 3 flavours lowest in phos but still with high
quality protein from proper meat sources. If you feed high
quality protein the amount of phosohorus is lower than a corn or rice based protein source.
Would you consider feeding a raw meat diet?
Has he visited the litterbox yet?