First do you know that Layena IS just a type of Purina? I feed Purina Flock Raiser pellets. It is 21% protein. All but my young chicks are fed this. I also offer oyster shell and grit free choice. This is just my method. I am not saying it is the best or any better than other people do.
Really? Nope - didn't know that. I thought they were separate companies. That's funny.
My birds have oyster shell on the ground to peck at and a dog bowl full of grit. Once I mixed the two together, and they didn't like the oyster shell in the bowl. Picky birds.