I recently started using kelp. I can buy it in a 50lb. bag for $15, so it's pretty cost effective. I started using it because it, along with paprika, is included in all "dark" horse supplements like Black as Knight and Nu-Image Dark Horse. It was also recommended for use by a trainer in my area. My husband's horse is a terrible cribber, but the cribbing lessened dramatically when I started the kelp. I don't think I've been using it long enough to see other results, especialy since the main reason I started it, sun fading, was already well on it's way when I started. I'm also not sure how much I'm supposed to feed. I don't have a scale to feed by weight. I have the same problem with the paprika, can't weigh it and don't know how much to feed to keep my Paint black. I might start anothter post asking how much to feed, not by weight, but my measure, i.e. cup, tablespoon, etc. if I can't find the answer by searching the forum.