API Pond AlgaeFix controls many types of green or green water algae, string or hair algae, and blanketweed in ponds with live plants. This powerful and fast-acting treatment controls existing algae, and helps resolve algae blooms. Registered with the Environmental Protection Agency, AlgaeFix is safe for use in ponds, fountains, and waterfalls, and may be used in ponds with live plants and fish. Use API for a clean, healthy pond all season long!.