X2, there are a number of threads on feeding mixed flocks, this is a nice one with guineas and chickens (a lot is talking about starting with babies, but a number of posts also cover adults) https://www.backyardchickens.com/t/...r-guineas-when-they-are-part-of-a-mixed-flock Most people seem to wind up feeding a Flock Raiser type food around 18%-20% protein with oyster shell on the side, or just feeding everybody Layer.
Thanks! So far I have just been feeding every layer and oyster shells on the side as well. They free range at least a couple hours everyday and get a variety of fruits & veggies as well. I just worry about the long term effects of the extra calcium on my rooster and guineas.