Envii Septic Klear &ndash; Septic Tank Treatment Uses Enzymes to Eliminate Odors - (12 Months Treatment) Helps prevent septic system backup by effectively degrading grease, starch, protein, and tissue on an ongoing, long-term basis Helps reduce septic tank odors by continuously breaking down the odorous volatile fatty acids and other odor-causing organic buildup. Pre-measured fast dissolving tablets. No mixing, No measuring, No spill, No mess! Simply flush it down the toilet. Made with plant based ingredients. Completely biodegradable. Phosphate Free. Ultra concentrated for less packaging. Safe For All Plumbing. Contains 12 tablets. Each tablet treats septic tanks up to 1, 500 gallons for one month