MICROBIAL ALGAE CLEAN algae control is an alternative approach to algae control and reduces pond maintenance. MICROBIAL ALGAE CLEAN algae control was the first bacterial algaecide registered with the Environmental Protection Agency. This product contains patented bacteria and controls green water algae in Koi and goldfish ponds containing live plants and fish. MICROBIAL ALGAE CLEAN algae control breaks down dead algae and improves oxygen levels. MICROBIAL ALGAE CLEAN algae control promotes a cleaner pond environment by eliminating troublesome organic sludge and debris, and will not harm plants or fish. Directions Add to the pond, one teaspoon for each 50 gallons or 0.25 cup for each 600 gallons twice a week for the first two weeks, then add once a week to maintain control of green water algae (Chlorella).