
Hi,
If your dog is not doing well on Hills, then you are paying a lot of money for little benefit :D
As Melodysk says, you will need to find a food that suits your dog. A large proportion of the most successful Dane breeders use and recommend the Skinners range of foods - these are reasonably priced, and seem to suit Danes well.
You may also find that you are feeding a little too much?
Marina