Despite what I read and others say, many of my bettas don't live long, 6 months to 2 years for that occasional one. They have been bred so intensely and are probably terribly inbred. The fancier the variety the less hardy they seem. There are still some short tailed and wild type that are a bit more long lived. It can help to keep them in a heated tank around 85-90, they suffer in any temperature fluctuations, they evolved in hot shallow pools of water, hence the reason they are air breathers.