I have six pullets. Three Ameracaunas, one Olive Egger, one Silkie and one Cochin. Everyone except my Cochin is between 3-5 months old. I think my Cochin is between 6-8 months old. I have been feeding them an always-available supply of medicated chick feed plus a daily treat bowl with a mix of cracked corn, black sunflower seeds and dried mealworms. I know I need to transition them off of the chick crumbles. Should I start them on layer crumbles? And how much is too much of the “treat mix” I’m giving them? Thanks for your input.