I did not know about the rumor about wellness core and crystals, but I will tell you this. I am a big believer in feeding only wet foods, but I do have one cat, who was a former kibble-o-holic, and she does get a small amount of kibble before bedtime, I'm talking like maybe 10 little kibbles. She is 10 years old, and recently had extended blood work done, and all looked really well, kidney functions were great, but the vet did say that she had some crystals in her urine. And she eats canned food, in small amounts, 3x a day, plus the kibble in the evening, and it is Wellness Core. The vet did say that it could be that the crystals were from the urine sitting before it is tested and he was not overly concerned about it, and she does only get a small amount, but I wonder if the WC dry is to blame for the crystals? Or it could just be that any dry food is causing this problem. I would actually tend to believe dry food in general, rather than to pick on Wellness Core. I do feed Wellness canned, grain free, and not the core, to all of my cats.