I'm trying to figure out my feeding program here! Normally I feed once a day, enough so that they still have some there in the evening. Is this enough? I have RIR, barred rocks, and a couple call ducks in that pen. The pen is about 20' x 50' plus the coop ( 8' x 14' or so) that they roam around. I just want to make sure they all get enough! They all come a' running when I go to feed, but then again, I can go in the house and come right back out and they still think they need feed even with food still there! I'm feeding layer crumbles and cracked corn if that makes a difference. Thanks!