They do make a "show verison" of Black as Knight. It doesn't have the paprika or any other banned substance that will test positive when showing. So you could try that. Personally I've always had better luck making sure my horse is on a good diet and adding something like flaxseed for a great looking coat. If you're trying to stop your horse from bleaching out I would just add paprika but be sure you pull them off a week before a show.