Article in English: Betta fish are members of the Anabantoid family (gouramis are also in this family), also called labyrinthian fish. They have a back-up breathing system that allows them to breathe surface air; however, they still require a filtration system in their tanks. Female betta fish are typically smaller than male betta fish. They usually lack the long finnage that males possess. However, they can still be equally as beautiful in their own way—–and feisty! Don't keep them together though, as females still tend to be as aggressive as the males. Bubble nests (foamy bubbles on the surface of the water) mean that they are getting ready to spawn. It does not automatically mean that they are happy or healthy. If a male likes a female, he flares his gills, twists his body, and spreads his fins. If a female likes a male, she wriggles back and front. "Betta" is actually a genus of fish. The typical betta found at pet stores is the Betta splendens species. There are actually many more species mainly found in the wild, and they can look like a totally different type of fish! Don't be afraid to choose a female betta fish! Although you may not be planning to breed them, a female is always less expensive and less aggressive. Therefore, you can always buy a female if you are inexperienced at keeping bettas, it is better to choose a female.

Summary in Vietnamese:
Một vài điều rất hay ho về loài cá Betta chọi này: