I would test for the Fanconi now then at least you know clear,carrier or what. There is lots on here about it but just for you and your dog I would do it. Go to www.offa.org and left side in the blue go to OFA-DNA Testing that will take you to the OFA Store and the 2nd one down is the Fanconi test you can order and do it at home and send it back to them.
We feed Jayce Eukanuba Lamb-Rice, Eukanuba puppy original and Peidgree Puppy we mix all three and she has done great on it. I must say she loves the Lamb and Rice the most but eats all three.
My cousin is a breeder and she feeds all of her dogs a can of green beans every week says its keeps there system clean and healthy. Her husband is a doctor and told her to do this went she started out about 20 years ago. Now just because he is a doctor does not mean that he really knows anything but she does have healthy and very long life dogs. Food for though.