Betta Fish, also known as Betta Splendens, Beta Fish and Siamese Fighting Fish, are inexpensive pets and can be quite lovely. Technically, the Betta name refers to about fifty species, but is commonly used as if only Betta splendens is meant. The biggest are normally only around three inches long. Even though there are many stories of the fish surviving in very small containers, experts do recommend a three-gallon tank for best results and there is some controversy about how small a tank is really still acceptable. Betta Fish are native to low oxygen waters, and don't normally need any aeration. They are tropical fish, and are best kept warm, however. Some owners do claim that their Bettas act happier with an air filtration system even if the fish don't need it to survive. Bettas normally live two to three years, but in well cared for conditions, some have lived as long as ten.

Betta Fish are native to Thailand and Cambodia. The common name comes from the name of Siam, which is now Thailand, and the territorial battles the males conduct. Like many members of the animal kingdom, the males are the gaudier looking, to better attract females. The females tend to appear rather dull, and almost all Betta Fish sold are males for that reason. In the wild, they are dull greens and browns, but breeders have produced far more stunning color schemes.

Some believe that Bettas cannot be kept with other fish. This is not true. Multiple male Bettas is a precondition for battle. Bettas with other fish around will still display and flare their fins, but won't see this as a mortal insult. They should not be kept in a tank with fish that are aggressive or that nip fins, and only one male should be present. Female Bettas can usually play well with others, and there are cages to be used to separate male Bettas if they are kept in the same tank. These should prevent the fish from seeing each other.

Betta Fish can handle a surprising range of water conditions, but the water should be changed once a week or so, more often if the fish is kept in a small container. They can be fed once a day, or twice if you desire, and aren't especially fussy about their food. There is specially formulated Betta food on the market. In the wild, Bettas eat live food, insects and their larvae, and like it in fish tanks, but they will eat flakes and frozen food as well. Do not overfeed as this will require cleaning the tank more often. When changing the water, remember to let the water sit for a day before using it in the tank with the fish to allow the chlorine to evaporate. Good choices for Betta food are brine shrimp, Daphnia, plankton, tubifex, glassworms, and beef heart, and may be used frozen or freeze dried. Flakes should be supplemented with other foods from the list.

Many note the odd bubble structures that male Betta Fish build in the water tank. This is perfectly normal. The male is building a nest in which to place eggs, once he successfully impresses a female.

Bettas prefer a pH between 6.8 and 7.4 and a hardness less than 20 dGH. The temperature should be between 75 and 86 degrees, or twenty-four to thirty for those who prefer Celsius. In the wild, they live in rice paddies, ponds and slow moving streams, and are most comfortable near the surface. One of the main arguments about the minimum size for the fish's tank is heat. Below 75 degrees, the fish are increasingly listless and it is much easier to keep a larger tank at a stable temperature. Bettas also require access to the surface, and will drown without it. There is a special organ, the labyrinth organ, allowing and requiring them to take oxygen from the air. Because they live in still waters, power filters and power heads are not suitable.

Betta Fish are known for their lovely colors and fins, with a wide range of colors available. Blue to red with white are normal, and more spectacular colors like yellow and orange exist.

Metal poisoning easily kills betta fish, and exposed metal should not be used in decorations within the tank. Decorations are important as they allow the fish places to hide, and a layer of gravel helps to provide surface area to grow nitrifying bacteria. Decorations must be smooth and lack sharp points that can tear fins. Silk is preferred to plastic for artificial plants for this reason.