Hi, I'm no expert, but I worked in the veterinary field for 8 years as a tech assistant/receptionist. Any time you want to switch foods, it has to be done gradually so that there isn't any problem. You first want to start off 1/4 new with 3/4 old for a few days, then 1/2 & 1/2, 3/4 with 1/4 old, etc. I suspect that your puppy was eating so much of the new food because it was something different for a change, just like people would welcome a different taste rather than the "same old thing". My vet, who happens to be one of the doctors that I worked with has recommended Royal Canin puppy mini bits for my new puppy. I'm feeding him 1/4 cup two to three times a day, depending if he's interested. I switched him over with no problems. I hope this helps you somewhat.
