I keep the feeder out 24/7 in the coop. Mine free range all day every day, but like you I have too many for them to get all they need from what they're able to find on their own. With 23 birds they will still need to get most of their food from what you provide. I find my crew mostly fills up in the morning and evening with the laying hens grabbing a snack when they come into the coop to lay.