We have 20 chickens and are using a large plastic feeder that we fill in the center and the feed comes down into a red dish at the base. Problem is that I am finding an awful lot of feed on the ground in the pen that is not getting eaten. Sometimes they knock the feeder over and it spills, sometimes I guess they just scratch it out and it's always possible that my kids are careless when filling it. What are good feeders that are better at preventing so much waste? Any tips (aside from train the children to pay more attention). Are the trough feeders better?