Algaefix- Quickly and effectively helps control algae and green water algae blooms, along with string algae and blanket weed algae. Great for use in synthetically lined ponds, fountains and water gardens where there is no outflow. Will not harm fish or plants when used as directed. Fast acting formula keeps ponds, fountains and water gardens clear and clean. Make sure to aerate pond when using. Aeration is essential while using Algaefix, especially in warm weather when water temperatures are high. Eight ounces treats 2,400 gallons. Do not use with crabs, lobsters or shrimp.