I have a few different age groups in chicks. I have 8 week olds, 6 week olds, and 3 week olds. When can I start giving them grit? The 8 weekers and 6 weekers are already in the coop but I have them separated for now until they get integrated. Should I have been giving them grit all along? I have raised many chicks before and never have given any grit until about 20 weeks old. I saw chick grit today and never knew it existed until now... should I give chick grit to all the chicks? Or just the 6 and 8 weekers? Thanks!