Aquaclearer™ Extreme Liquid 16OZ treats up to 48,000 gallons. Adding bacteria periodically to a water feature is one of the most important things you can do to maintain clear, healthy water. Add bacteria in the spring to start your system, in the summer to spike it periodically and in the fall to maintain it. Bacteria is all natural and not a chemical! It's safe for fish and plants. Directions on how to use it come on each bottle. Dry bacteria has a longer shelf life of two years as opposed to liquid which is one year, although liquid is faster acting on new ponds than the dry. Aquaclearer™ Extreme Liquid 16 OZ 2780724010 Most Orders Shipped Out Same Day! Premier Ponds PO Box 33 North Salem, NY 10560 1-877-669-9078 pondinfo@premierponds.com U.S.A.