I've been on the site reading a jabillion messages trying to educate myself on various issues...I know that i need to give my layers oyster shells, but cant find out how to feed...do I mix it into the layer pellet or serve seperately...if its a mix, what's the ration??...also, Molly was laying eggs every day, and hasn't in 3 weeks...is this because she hasn't had oyster shells??? Any insight would be greatly appreciated.