Betta Fish – The Betta fish is probably the second most popular fish kept, after Goldfish. The Betta Splendens is a favorite because of its beauty, its long fins and because bettas are relatively easy to care for. The male sports deep beautiful colors whereas the females are less colorful. Their stunning colors and flowing fins are some of the reasons for their popularity.
Betta fish are called the Siamese Fighting Fish because of its behavior towards other males of the same species. You cannot keep two or more males in the same tank. If more than one male fish are placed in the same tank, they will fight until only one of them remains. They will flare out their gill covers and erect their fins showing the other fish their fighting posture.
This behavior is also why they are kept separated in small containers at the store. There are ways to see this behavior without introducing another male betta fish. One way is to use a small hand mirror and place it up against the tank glass so that the male may see his reflection.
The Betta will mistake his reflection as another male and the fighting posture should then be displayed. Doing this too often may lead to an overly stressed fish though. You can get small tanks that come with dividers which will allow you to keep two in the same tank. Many keep them in a small betta fish bowl and they may live for a while in these small bowls.
However, to get the most beautiful colors and optimal health for your fish, they will do better in a 10 gallon or larger betta aquarium with a heater that can maintain a constant temperature in the aquarium. If you plan on keeping yours in a small betta aquarium, make sure to change 50% of its water every week in addition to introducing a small aquarium plant to help keep the water clean.