It often seems that the designer pet foods which promote themselves as rich in nutrients cause GI upsets. I prefer high quality foods without the gimmicks. Here is a short list:
Natures recipe c d
Iams woof soft
Iams Eukanuba small bites d
Royal Canin c d
Pro plan savory soft
Hills ideal balance c d
Castor pollux organically
Simply nourish c d
Wellness c d
Bil jac frozen
c-can d-dry kibble
I do not set the terms of your warranty, you should check with the people that provided your puppy and back the warranty.