Mine have outgrown their 3" pvc ports and the 4" curved pvc ports that I tried to use are so clunky and heavy they won't stay put, and they aren't as effective at holding the feed in. I'm seeing so many other options out there, show me your favorite!
My rooster is a no waster. He would eat from anything and leave nothing afterwards. But basically, feed bowl outside and little windows for the head so he is able to grab the food.