Is there any other dry food that is comparable to Hill's prescription
s/d? One of my cats has a bad UTI and I bought a small bag for her, but
my problem is that I have 7 other cats and they can't eat this food. I
plan on feeding Sasha (the one with the infection) the Hill's food until
 the infection is cleared up, but I would like to find a food that will
be good to help keep her healthy and the other cats can eat it too.

I was thinking of Pro Plan for urinary tract health. I looked up the
amounts of ash and magnesium and they are lower that Hill's s/d. Are
these the only two ingredients I should be concerned with?

Thanks!

Missie