How much protein for 8lb 5yr male Maltese/Pomeranian mix?

I'm changing food from Bil*Jac to Buffalo Blue Holistic and both are 26% Crude Protein. Is this an appropriate choice for my little guy where his kidneys are concerened? I had a yorkie that developed kidney failure around age 12 and I couldn't find a decent brand of dog food that was low in crude protein. Fritz & I thank you in advance!