I have 11 laying hens and a rooster. Just introduced 7 week old babies a few weeks ago. Their wooden brooding box is in the coop. Everyone free ranges during the day an all get locked into the coop at night. I have the big birds on layer crumble and the babies on Purina Start and grow. They seem to eat each others food. Any ideas on what to feed them so there is no mix up? I do have oyster shell available in a small bowl that nobody has touched in 3 months!!! What do you all do for mixed aged chickens in the same coop?