They are called Siamise fighting fish of betta It is part if there nature that they fight. It depends on how large the tank is if they can live together or not. It also depend on the betta some can some can't. Females can live together if there are three or more. Males it depends there are calm bettas wich still attack but can live on a big tank with another male. Then there are aggressive bettas wich attack and probalbly should not be put together. If you put a male and a female together they might breed or the male might just chase the female around. If that happens take the female out and try again in a few more days buy unless you know what your doing it is advised that you don't try breeding bettas
hope that helps

• Why will beta fish fight if they are in the same tank or fish bowl?
• So just out of curiousity, if you clean a fish bowl/tank with soap can you ever use it again?
• For my commet gold fish can I just but it in a fish bowl ?
• I heard that if your fish aren't feeling to well, you put some peas into the fish tank and they get all better
• Does this Dechlorinator work for all fish? New fish tank mates?
• Do I have to Much fish in my tank and can fish live without a heater?
• If i acidently put juice in my fish tank will my fish die?
• When fishing for salmon are you allowed to clean the fish of the fish eggs then throw fish back in water?
• Angel Fish? Cat Fish? Or Gold Fish? which type of pet Fish do you like better?
• I have to many fish in my tank will it kill my fish?