Roebic, 32 OZ, Septic Tank & Cesspool Bacterial Cleaner, Cleans Sluggish Septic Tanks, Cesspools, Drywells & Drain Fields, Bacterial Cultures Which RestoreOperating Efficiency, One 32 OZ Bottle Treats 500 Gallon Capacity, Certified Biodegradable By Scientific Certification Systems, Biodegradability Achieved In 10 Days.