Biofilter Booster is a highly concentrated solution of live bacteria that start up and maintain the biological filter in water gardens and koi ponds. Goldfish and koi continuously release harmful ammonia into the pond. Uneaten fish food and decaying algae also cause ammonia and nitrite buildup. The beneficial bacteria in Biofilter Booster quickly establish the biological filter and begin breaking down these harmful substances and improving water quality. Regular use of Biofilter Booster helps the biological filter remain active all season long. Directions For Use: Spring Start-up and New Ponds: Shake well before using Add 2 teaspoonfuls (10 ml) for every 25 U.S. gallons (95L) of pond water directly into the biological filter once a week for 4 weeks, or until water tests for ammonia and nitrite remain at zero. Summer Directions: Add 1 teaspoonful (5 ml) for every 25 U.S. gallons (95L) of pond water directly into the biological filter once a month. If water testing indicates dangerous levels of ammonia or nitrite, revert to "Spring Start-up" directions while corrective measures are taken. Compatibility: Biofilter Booster can be used with koi and goldfish, frogs, tadpoles, snails. And aquatic plants. Biofilter Booster can be used in ponds and water gardens where wildlife comes to visit. Keep from freezing. Do not store above 120°F (49°C). Biofilter Booster has a five year shelf life and does not require refrigeration.