Your hivetop feeder must be treated in order to prevent the syrup and wet weather from causing warpage and/or leaks. When applied properly, this product will keep your feeder looking and working great for years to come, and as long as you allow sufficient time for it to cure before putting the feeder to use, it will not harm your bees in any way. Treating a single hivetop feeder requires about 2/3 of a can.