TetraPond AlgaeControl is formulated to effectively control algae blooms (green water), string and hair algae (spirogyra) and blanketweed (oedosonium) in fountains and ornamental ponds with synthetic liners. When used as directed, TetraPond AlgaeControl can be used with plants and ornamental fish. Before using this product, dislodge string algae off stones with a high-pressure hose nozzle and scoop out with a fish net or pond vacuum. Ensure your pond is well aerated. See the product label for complete directions for treatment. Algae are primitive plants that, via photosynthesis, combine water and carbon dioxide to form sugars for energy and growth. Algae can obscure colorful fish and deplete valuable oxygen. No pond is ever totally free of algae, but in a balanced environment and with the right treatment methods, algae can be kept in check. Since 1951, Tetra has developed the worlds most comprehensive body of fish food knowledge, and fishkeeping enthusiasts have looked to the brand for products and solutions that add ease and beauty to their home. Whether youre an experienced hobbyist or just starting out, Tetra has everything you need from a large variety of quality fish food and innovative equipment to test kits and decor.