As a breeder, I have tried several different types of puppy food. The one that has been an instant hit with all our puppies over the years has been "Eagle Pass Holistic Select." At four months, he does need hard food, but you should mix some canned foot with it. Also, you might look at changing the hard food ~ we feed our puppies Nutra Natural Choice Puppy food, and they like that also. The Eagle Pass is Puppy Chicken and Oat Bran Formula and it can be ordered online at:
Pet Food Supplies Dog Cat Bird ... PetFoodDirect.com.
Helen