My dogs have been on Whole Earth Farms (by Merrick) dry food for a couple weeks now and are doing great. It is normally really affordable, but was on sale at Petco and came out to $1/lb. It is not grain-free, but doesn’t have corn. It’s a 4 star food on here, and my dogs love it. I got the 35lb bag for $35-something. Their wet food is great too.
My dad also just got that grain free stuff from Costco.. Nature’s Domain? His dogs haven’t been on it long enough to know how they do, but it is also very affordable. I think it’s rated a little lower but it is grain free.
