Hello, and Welcome to you and to Derby..... @ 8 weeks old, I know your in for the ride of a lifetime, These little guys come with so much personality pre-installed, Their a wound up ball of energy with their bullyness, lol. Your going to be just like us now, and addicted, But it's okay, Hold on, strap in and enjoy this site, it's the most experienced website on the web for our Pets, I stopped by here also, researching foods, and became an instant fan, these guys are like Family, and Derby will surely reap the benefits......Onto your food question, Their tummy's are so sensative, its hard to believe. When I first got my Rocky, he was on Purina, So I bought Purina to start with, I was using small kibbles instead of the large he was use too, and a different formula evidently, and it tore his tummy up. After a trip to the Vet for medicine to calm his tummy down, I was able to move him onto Blue Buffalo sensative formula (Grain Free) help with Allergies, Only to find it had chicken, and didn't have much protein in it. After researching the food Ratings page under articles, I found most here use Fromms, Beef Feritta or Pork and Peas, The really exciting thing is, Fromms really caters to our pets, They offer nutritious foods, ones they will eat, and they do a lot of research for their ingredience, and if your using one of their 4 Star Foods, you can feed one Flavor in the morning, a different that evening and don't have to worry about the transition. I use Blue Buffalo, which is readily available to me without mail order, but through here you can get a code for free shipping on foods over $50.00 I believe, not positive, and of course you know most of the time, depending on your state, you get away without tax, just sayin....Food changes are difficult, and best put, should be done in 9-10 days. Start out with 1/4 cup new food, and 3/4 cup old food, for 3 days, Then 50/50 for 3 more days, then 75/25 the finaly 3-4 days, then 100%. There poop should remain consistant, Formed, but not runny, Firm !! The science Diet i once thought to be a good food, and is mostly peddaled by Vet's who receive kick backs on the sales, and once upon a time was one of the best foods on the market, Today with all the research, Lab tests etc, nutrients and vitamins, protein and everything else considered, put Hills Science Diet pretty much out of the running. The trick here is to find a good food, Like many of our breeders use the Fromm's Puppy food in the Pink Bag, and then at about 7-8 months of age switch over to an adult food kibbles. On here you will get a lot of great information, and you'll see we all do things a little differently, Point being, find a great food for your pet, that wont interact with his allergies, and go with it.... Slow Transition is Best.... and read, Read, and Read more of the articles here, and learn all you can, you and Derby will both benefit so much !!! and last....Welcome to our Family !!!