I have been feeding my babies medicated chick starter but it is getting very expensive to buy chick starter and layer crumbles. This time I bought 4 bags of scratch grain and a side bag of oyster shell grit. I didn't look up what everyone said to buy before we left and when we went round the side to pick up the food, a man was picking up flock grower and I remembered that was what someone said to get. Problem is the bags he got also said crumbles on it. Without you being able to see the bags, what is your best guess: did that flock grower crumbles contain calcium? Is the scratch grain I bought totally the wrong thing for my adolescent and adult chickens? At what age is it safe to stop feeding medicated chick starter to my chicks? I want to switch them to the adult food that doesn't contain the calcium and put the oyster shell on the side for the laying hens. I forgot to add that they do forage during the day and they are all ages up to 2 1/2 years old.