I second what Patty said to 99.9% (my pup has been on Blue Buffalo Wilderness Puppy for a couple months and he has done great on it, no diarrhea (VERY firm stools actually)), but being cautious wouldn’t hurt. My personal preference is for grain-free foods, which is what most of the 5-star dog food for either adult dogs or puppies are.
Another advice – take the time, read reviews AND comments, AND the forum – it may be overwhelming at first, but if you develop a structure/way to do it, or even better, a passion for researching what is good for your pet, it will become easier to handle. Lists are great, so do that and keep an eye on how your dog is doing on a particular food, and an ear out for food recalls. You can sign up for the free recall alerts on this website. Also, if you find at least one great food for your pup, you will probably find at least a few more good ones, and rotational diets seem to be highly-recommended for optimal dog health.
