After our last cat had kidney issues, new cat gets wet food daily. We basically go 50/50, half wet food half dry food. That works out to half a 5oz can a day, 1/4 in morning and 1/4 in evening. She normally eats the wet food within ~15 minutes and nibbles the dry food throughout the day. Not sure if it helps her kidneys but she has maintained a good weight and has the softest coat.

We also use a water fountain to try to encourage drinking, but I don't think she drinks any extra because of it.