What can I do to prolong the life of my betta fish as long as possible

OK - I have now had mine about 6 months and these are the key things. This answer is a bit long and all over the place but if you do all of this he or she will be one happy fish for years to come. =) Some people's answers will probably be too simple and he will get sick if you listen to them - really. I tried that route. It is a tolerant fish but he can be sensitive so these things are a must - keep them stocked in case you ever need them but you shouldn't if you use these products and follow the directions and dosages carefully. =)

I use the All -Glass brand( though it is made of acrylic which is good) 2.5 MINIBOW tank and replaced the filter it came with with a Red Nano Sea Filter (petco.com) - much clearer - just much much better. I love this tank - it is great, comes in all different colors and you can upgrade if you want to in the future. It is also very easy to carry even when full - just convenient - the perfect size. They sell it with a divider so you can put one betta on each side but I think that is mean so I wouldn't do that :( Also this tank is great cause the 15 watt light bulb warms the water a bit - which betta like (76 to 82 degrees) - If you find that this is not sufficient, you can change the bulb to the 25 watt - I change them back and forth depending on when I use the air conditioner, etc - It really works well. DO NOT get a heater - that will get the water too hot and you as the pet store guy told me will make betta soup - (if your tank is over 5 gallons, you may need a heater though) But for a 2.5 gallon, the bulb is perfect! If you ever find the water is too cold, do a quarter or half water change and just add some warm water with the conditioner and it will be fine.