Well everyone else here has pretty much said what I would have said!
My cats get mainly a dry food diet, of Felidae. They get the occasional wet food (various brands, there is nothing good in this town), about every 3 days as a treat.
My cats however drink plunty of water, I know not all do.

Some of the best cat foods, which can also help prevent health problems from starting...

Felidae
Innova
Chicken Soup for the Cat Lovers Soul
Evolve
Holistic Blend
Natural Balance
Nutro Natural Choice
Natures Variety
Pinnacle
Solid Gold
Wellness