The Siamese fighting fish, also known as Betta fish, is a popular freshwater fish native to Southeast Asia. They are known for their vibrant colors and long, flowing fins. Males are particularly aggressive towards each other, which is why they are often kept alone in aquariums. These fish thrive in warm water and prefer a well-planted environment. They can breathe air from the surface due to a special organ called the labyrinth organ. Siamese fighting fish are also known for their unique behaviors, including bubble nesting and displaying their fins to attract mates.