Definition of theory. plural. theories. 1 : the analysis of a set of facts in their relation to one another. 2 : abstract thought : speculation. 3 : the general or abstract principles of a body of fact, a science, or an art music theory.
Studies have also shown that those Betta Fish which live in larger tanks will probably live much longer than those who are cooped up in smaller tanks. In fact, if you are purchasing any tank you should always purchase the largest that you can both afford and fit into your room. This is going to benefit all of your fish. Hopefully this has been of some use to you and provide at least a couple of answers as to how long does a betta fish live.
In the wild Bettas generally grow to 6.0 cm (2.3 in.), however many are now bred up to 8.0 cm (3.5 in.) in length. A Bettas diet in the wild generally consists of insect larvae such as mosquito larvae. It is noteworthy that many of these insect larvae feed themselves on green organic matter, so a proper diet should consist of food that duplicates the digestive contents of these larvae as well. Betta fish can live for up to 8 years in the wild, but this is rare with all the risks they also face in the wild.