I have Red Sex-links, as well, and mine wasted a lot of feed...until I built a gravity feeder out of 4" PVC pipe with a "Y" on the bottom. No muss, no fuss, and no more wasted feed.
Weird about the sex links being messy. I have a red and a black and they're the two neatest eaters! I have more issues with my Barred Rock knocking the food over and generally making a mess.