I have 4 nine week old chicks and a 6 month old pullet. The 6 month old pullet is currently in quarantine so it's no big deal to feed them different things. But when I eventually have them all together I was planning on feeing them a Flock Feed and provide oyster shell as I have seen recommended so often on here. I figure by the time they are all together thy will be 3+ and 7+ months old. When I went into Tractor Supply today I found Purina's Flock Feeder. But the folks at Tractor supply said that wouldn't work. What am I missing? Is there a guideline on how much protein and other nutrients should be in a flock feed and then how much additional calcium a layer needs?