The family Pomacentridae, commonly known as damselfish, includes small, colorful marine fish found primarily in coral reefs. They are known for their vibrant colors and territorial behavior, often defending their nesting sites aggressively. Damselfish play a crucial role in reef ecosystems, contributing to algae control and providing habitat for other marine species. There are over 300 species of damselfish, with notable examples like the blue damselfish and clownfish. These fish typically exhibit a range of colors, including blue, yellow, and orange. They are popular in the aquarium trade due to their hardiness and striking appearance, making them a favorite among marine enthusiasts.