Freshwater tetras are a popular group of small, peaceful fish known for their bright colors and active swimming behavior. They are a type of characin fish native to South America, but are now widely bred in captivity and available in many different colors and patterns. Tetras are generally hardy and easy to care for, making them a popular choice for beginner fishkeepers. They are schooling fish and should be kept in groups of at least 6 individuals to promote natural behavior and reduce stress. Some popular species of freshwater tetras include neon tetras, cardinal tetras, black skirt tetras, and serpae tetras.