All natural, 2 month septic tank treatment works to reduce septic system backup. Bacterial action helps break down household wastes, fats, oils, and greases. Helps to reduce harmful sludge build up in septic tanks and field drain lines. Environmentally biodegradable ingredients. Helps to stop unpleasant odors. Safe for all plumbing. Use 16 oz. for a 1000 gallon tank every 2 months. Simply flush product down toilet bowl. 16 oz.