Mustard algae, also known as yellow algae, is a common problem for pool operators, primarily in the southern region of the United States. Unlike green algae, mustard algae appear as yellow or brownish spots and cling to pool walls, floors, and swimming equipment, making it difficult to remove. Understanding how to identify, prevent, and control mustard algae can help maintain a clean and safe swimming environment. In this article we're going to explore a comprehensive approach to managing mustard algae in your pool.