I have 3 chickens that are nearly 6 months old ( not laying yet). They have a 10x10 foot "caged" area to forge in, but escape daily. I move the tractor about every 2 weeks, but it is just lawn. I have been making (read crazy lady who bakes soy beans) and mixing feed for them, but have not keep track of how much I'm actually feeding them. We through the feed into the cage when we let them girls out every morning. Sometimes they leave some of the feed untouched. Could I be over feeding them? How much feed should I be giving the?