Puppy cannot handle natural dog food...help!!?

We had a problem with our young Dobe, too. We were feeding Merrick, but changed over to Natural Balance. There is Potato in the formula we feed, but no grains. That is what I *think* was causing the problem. This might not be the answer for you, but I just thought I'd share my experience. I believe the Merrick is a better food than Natural Balance, but you have to feed the dog with what works for that individual dog. (It's the Potato and Duck formula that we feed her)