Roebic, 32 OZ, Septic Tank Treatment, Anaerobic & Aerobic Spore-Bearing Bacteria With Aerobic Vegitative Bacterial Cells Selected, Conditioned & Cultured For Use In Septic Tanks, Continually Produces Enzymes Which Digest Protein Keeping Tank Contents Liquid & Prevent Over Accumulation Of Organic Waste, Resistant To Soaps & Detergents, Use One 32 OZ Bottle Per 500 Gallon Tank Capacity to Prevent Clogging For 1 Year, Certified Biodegradable By Scientific Certification Systems, Biodegradability Achieved In 10 Days.