Grains are the biggest problem from what I've seen. Look at the can/bag.
Its usually the number one or two ingredient.
Evo, Innova, Wellness, Merrick, Taste of the wild .... There are many that are good.
The cost is the issue though.
This is a good link to check out
http://www.dogfoodadvisor.com/
Nirvana!!! Please weigh in, I'd like your opinion.