Will Nemo eat canned or wet food?? You might try that first to see if he'll like it.
When we got Ranger the breeder was feeding him Mighty Dog chicken and rice, she told us that he got sick eating anything else
. So that's what we fed him for about a week before I went and bought Science Diet Puppy chicken and rice. I added about two tablespoons to his Mighty Dog and he didn't even seem to notice, nor did he get sick. Over a week I had switched him to the Science Diet and he had no problems. After a month I bought Science Diet Puppy dry food and slowly began adding that to his wet food. Two weeks later he was eating the dry food by itself and wasn't being picky.
I'd also talk to your vet; sometimes they can give you free samples of different foods that are good for your puppy. Good Luck!!