Hi Kerri,
 
My ferts haven't developed crystals or anything, but my vet suggested
that I switch to only ferret food for similar reasons.  Mainly, he just
said that it was better for them.
 
Faith and the fabulous five,
Mischief, Dakota, Willow, Tundra & Chicklet
and dogs Baloo & Karma
[Posted in FML issue 3879]