For treating flowing and still water. These ceramic beads were impregnated with EM when they were made. The result is a clean and chemical free way to treat water to keep it clean and free from impurities algal build-up. Just add a handful anywhere you get green, slimy water. The ceramics are most useful in areas with running water, and if treated correctly, can be used indefinitley. In difficult pond situations treat with BLS Liquid first. Areas of use around the house would be flower vases, header tanks, or water butts.