I purchased some eggs from James Marie Farms a while back, and my chicks are now 3 weeks old. I called Robbie at JMF for some extra nutritional advice yesterday. He told me that for chicks you plan on using for laying hens at 5 to 5 1/2 weeks you switch them to a feed that has no more than 20 to 24% protein; and you should not add any extra protein to their diet. He said the bird food (He recommended Purina Gamebird Layena) had everything needed in it. If you give them too much protein the hens will put on extra fat around their reproduction organs, which over time would slow down their laying. When I asked him about the grit he told me that is another area many breeders make a big mistake with. He said the birds will like it, but over time they will end up with too much calcium which will, over time render the roos infertile, and will also hurt the hens.