Greenex spore-forming bacteria attach themselves to the cell wall of algae, denying them the very food supplies they need to survive. Patented self-dispersing formula reduces excess phosphorous, ammonia, nitrates, nitrite, calcium, and phosphates. It evenly self-disperses over the water surface for maximum effectiveness and ease of use. This 100% natural, water-quality treatment contains no petroleum chemicals. Use every two weeks throughout the season. Note: Unplug UVs for 24 hours when adding bacteria.

4.2 oz - Treats 19,500 gallons
8.8 oz - Treats 39,600 gallons
2.2 lbs - Treats 158,400 gallons
9 lbs - Treats 633,600 gallons