Pond scum, typically referred to as ALGAE, is a type of aquatic plant that grows in still or slow-moving bodies of water. It is usually green in color and can range from microscopic single-celled organisms to large, complex plants. ALGAE are an important part of the food chain, providing food for fish, birds, and other aquatic life. They also help to keep the water clean by absorbing nutrients and filtering out pollutants.