The Betta genus is a part of the Gourami family (Osphronemidae). Earlier, the Betta genus was considered a part of the Anabantidae family. The reason behind this is the fact that all Betta species have labyrinth organs, just like the Anabantidae species. The labyrinth organs make it possible for Betta and Anabantidae species to absorb oxygen directly from the air. It is an adaptation to a life in low oxygen waters. Some irresponsible fish stores sell Betta fish in vases and tiny bawls without any form of aeration, and claim that the Betta will do well in such a tiny space since the fish can breathe oxygen from the air. It is true that many Betta fishes will survive in such conditions, but there is a huge difference between merely surviving and really doing well. One of the most commonly kept Betta species, the Betta splendens, can grow larger than 7 cm (3 inches) and will require at least 3 gallons of water to do well.

Thailand is the Betta's natural home.  In the wild, they live in stagnant, low-oxygen bodies of water, such as pools and muddy streams. Waters temperatures in their native land range from between 25 and 28 C

Believe or not, Betta fish are not very aggressive in their native environment.  In the wild, Bettas only fight when they are defending their territories or mates, but these bouts of strength very rarely end in the death.

In captivity, a Betta's fighting activity is enhanced by space restrictions.  As mentioned above, Bettas are naturally territorial, so when they're placed together in a restricted area, such as an aquarium, there is a very high probability that a fight will break out.  And because there is not sufficient space to flee from one another, these fights end in the death of one or both fish.

Since the male Betta is extremely territorial several males should not be kept together in the same aquarium. It is better to keep just one male Betta with several female Bettas; as long as you make sure that the female Bettas have a lot of good hiding spaces in the aquarium. The male Betta is not only aggressive towards other males; he will chase the female Bettas around as well and without suitable hiding places the female Bettas will become much stressed. You can of course keep only female Bettas to avoid this problem, or keep a male Betta with nothing but other species that won’t be harassed by him. Betta is often kept with Swordfish, Platy, Angelfish and small Gourami species

Males are more aggressive than females, although females do fight with each other on occasion.

 

Choosing a Tank
The tank is your Betta's home - it's where he or she will be living 24 hours/day for the rest of their lives, so it's a good idea to buy a quality tank that isn't too small. Following specs when choosing a tank:
- Size: at least 10 gallons
- Material: Glass or Acrylic
- Shape: Rectangular
- Bettas are used to shallow water, not deep water.

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Remember, if you don't have your tank setup the right way, then every day that goes by is another day that your Betta is growing less and less healthy. Betta care is so easy when done the right way. Don't let another day go by without properly caring for your fish.  It's not fair to you, or to your pet. Betta care should be fun and easy, not stressful !