Siamese Fishing fish

The Siamese fighting fish (Betta splendens), commonly called a "betta," (pronounced 'bet-ah')is one of the most popular species of freshwater aquarium fish. It is native to the Mekong river basin in Southeast Asia and called pla-kad in its native Thailand.
B. splendens usually grow to an overall length of about 6 cm (~ 2.3 in), though some varieties reach 8 cm (3.5 in) in length.In recent years breeders have been able to create "Giant Bettas" that are 7 inches in length. Although bettas are known for their brilliant colors and large, flowing fins, the natural coloration of B. splendens is a dull green and brown, and the fins of wild specimens are relatively short. However, brilliantly colored and longer finned varieties, such as veiltail, delta, superdelta, and halfmoon have been developed through selective breeding.
The betta is a member of the Gourami family (family Osphronemidae) of order Perciformes, but was formerly classified among the Anabantidae. Although there are nearly 50 other types of bettas, B. splendens is the most popular species among aquarium hobbyists, particularly in the United States.

Lifespan
Normally, bettas live 2-5 years depending on how they are cared for. Male bettas living alone in large individual tanks and daily exercise have lived 6 years or longer in laboratories. Typically, males purchased from a pet store are over four months old, at a point when their finnage becomes fullest and most attractive. Due to their shorter finnage, females available in pet stores are often only 3-6 months old.

Breathing
Like anabantids and all members of the genus Betta, Siamese fighting fish have a labyrinth organ in their heads that allows them to take oxygen directly from the atmosphere in addition to the oxygen taken from water via their gills


Reproduction and nests
Females have an ovipositor, a small, white 'pearl' at the anus, most visible from below the fish. After mating, females lay egg clutches of approximately 100-500 eggs, rarely over 600 eggs. The male tends the eggs and newborns. Betta males build bubble nests of various sizes and thicknesses near the surface of the water. However, after the young fish are swimming freely, the male no longer tends to the young.
Due to their social patterns, bettas are difficult to breed. Most breeders prepare baby food and minnow-ready (cycled) tanks, prior to actual breeding in order to prepare for abandonment by the male parent and to improve the fish's actions such as speed, growth, and energy.
Males sometimes create bubble nests even in the absence of female and young. This may result from quick temperature changes, barometric changes, changes to materials in a tank, or the presence of other males or females.

Diet/Exercise



Bettas are top-feeders, but roam all depths of their shallow habitat.
Bettas have upturned mouths and are primarily carnivorous surface feeders. In the wild, bettas feed on zooplankton and the larvae of mosquitoes and other insects.
Bettas which feed upon a wide range of foods often live longer, show richer colours, and heal more quickly from fin damage. Betta pellets are typically a combination of mashed shrimp meal, fish meal, brine shrimp, bloodworms, and various vitamins. Bettas also will eat live or frozen bloodworms or brine shrimp or daphnia. For variety and fiber, some hobbyists feed bettas finely chopped vegetables high in protein, such as soybeans, green beans, broccoli, corn, or carrots. Although some bettas subsist on dried flaked food suitable for tropical fish, these fish typically reduce in colouring.

Tail shapes



A metallic, double-tail male Betta
Breeders have developed several different tail shapes:
Veiltail (non-symmetrical tail, only two rays)
Crowntail (highly frilled, extended spiny rays)
Combtail (less extended version of the crown tail)
Half-moon (large tail fin that forms a 180-degree, or larger, half circle)
Short-finned fighting style (sometimes called "plakat")
Double-tail (the tail fin is split into two lobes and the dorsal fin is significantly elongated)
Delta tail (tail span is less than half-moon with sharp edges)
Fantail (a rounded delta tail)

Colors

This pale pink male has red fins and splotches.
Bettas have been affectionately nicknamed "The Jewel of the Orient" due to the wide range of colours which are produced through selective breeding.

Recently breeders have developed in females the same range of colours previously only seen in males.

A green female.

Bettas have been affectionately nicknamed "The Jewel of the Orient" due to the wide range of colours which are produced through selective breeding. Wild bettas only exhibit strong colours when agitated. However, breeders have been able to make this colouration permanent, and a wide variety of hues breed true. Bettas come in a variety of colours, such as red, blue, turquoise, purple, orange (very rare), yellow, white, and green. Most are slightly iridescent, and can appear to change colour with different lighting or viewing angle. Breeders have also developed different colour patterns such as marble and butterfly, as well as metallic colours such as copper, gold, and opaque.
Breeders around the world continue to develop new strains. Recently breeders have developed in females the same range of colours previously only bred in males. However, females never develop finnage as showy as males of the same type and are almost always more subdued in colouration

Behavior

A male "attacking" and flaring at his reflection in a mirror.

Male and female Bettas flare or "puff out" their gill covers (opercula) in order to appear more impressive, either to intimidate other rivals or as an act of courtship. Females and males will display horizontal bars (unless they are too light a colour for this to show) if stressed or frightened. Females often flare their gills at other females, especially when setting up a pecking order. Flirting fish behave similarly, with vertical instead of horizontal stripes indicating a willingness and readiness to breed. Bettas sometimes require a place to hide, even in the absence of threats. Bettas may set up a territory centred on a plant or rocky alcove, sometimes becoming highly possessive of it and aggressive toward trespassing rivals.
On average, males are more aggressive, though individual females, especially crowntails, demonstrate a wide range in level of aggression. The aggression of bettas has been studied by ethologists and comparative psychologists[1]. Bettas will even respond aggressively to their own reflections in a mirror; use of a mirror avoids the risk of physical damage inherent in actual conflict.

Tank size

When kept in a small container such as a vase, the fish need frequent, sometimes daily water changes to rid the water of fatal ammonia build up which remains the main cause of death for the uneducated betta owner and the container must be kept in a warm room, at a steady temperature of between 76-85 degrees. Drastic temperature changes can put the betta into shock and may prove fatal. Temperatures lower that 76 degrees lead to lethargy and make bettas more prone to illness. A three-gallon tank is the minimum size tank in which a betta should be kept.
Fish of this breed are often kept in small containers, or even in vases as a display piece. Many bettas end up drowning as these decorative vases do not allow the bettas to surface for air. Many argue that they should not be kept in these conditions, that they are only sold in small containers because they will fight if kept with other bettas or incompatible fish. Such small containers are also used as a marketing tactic by many pet stores that promote bettas as a display fish and, incorrectly, state that they don't need much water and like smaller containers. It is recommended by these groups that bettas, like all fish, should have adequate filtration and have a heated environment, as they are a tropical breed and are prone to illness and death if not kept in conditions suited to their breed. These groups also frown upon them being kept in less than two gallons of water, as is often practiced when the breed is used as a display. They recommend that a living environment of at least five gallons is 'ideal'.
To maximize the lifespan of the fish and ensure their well being, they should always be kept in appropriately sized tanks. As a rule of thumb, for each inch of fish there must be at least one gallon of water in its tank. Bettas ideally should be kept in a filtered tank of five gallons or more and treated like any other freshwater tank fish.
Nonetheless, to keep an individual B. splendens, a minimum tank size of at least three U.S. gallons is recommended, if it will be kept in a warm room. Some authorities maintain that for a betta to lead a happy life and live the maximum lifespan, as much as five U.S. gallons is necessary.[2] This absolute minimum ratio (eight litres/fish) holds true for both females and males who are being housed individually as well as females who are being housed together; this means that the smallest tank that can become a female community tank is ten U.S. gallons, which can hold four peaceful females. A tank of five U.S. gallons will allow the use of a heater to maintain a temperature of about 27° C, or 80° F. It is optimum to keep the pH levels of the water between 6.5 and 8.0. One must take care in monitoring the pH levels to ensure the health of the fish, specifically if CO2 injection is being used in a planted tank, which can result in rapid spikes of pH values. Live plants will improve the water quality. Also, since the betta obtains oxygen from the air, the tank must not be covered with an air-tight lid and the betta must be able to easily reach the surface. It should be noted that the lid must not leave any gaps large enough for the betta to jump out. Bettas are notorious for their jumping abilities and there have been many recorded cases of bettas killing themselves. However, they have often been known to survive up to five hours outside the tank.

Tankmates

Two females in an aquarium. Males generally cannot cohabit.
Because of the aggressive nature of this species, a betta's tankmates must be chosen carefully:
Two or more Males: Contrary to popular belief, male bettas do not 'fight to the death' in the wild; once one fish has clearly won the encounter, the loser typically retreats to a safe location. In an aquarium, however, there is no place to run, so the winning fish continues to attack the loser, often resulting in death. Therefore, hobbyists rarely house two male B. splendens in the same tank unless they are (a) separated by a dividing wall, or (b) they are from the same batch of eggs and are not fully mature.
A Male and a Female: In the wild females tend to stay clear of males, except during mating. When cohabiting in tanks, males can kill females and are generally kept apart unless (a) they are juvenile siblings, (b) they are breeding, (c) there is a separator such as a piece of glass, or (d) the tank is large enough for the female to escape. Often, prior to induced breeding, breeders use such a container in order to allow a female to display without being harmed by the male.

Several female bettas in a community tank with mollies and rainbowfish.
Two or more Females: Bettas are not schooling fish, but with enough room and many hiding spaces, female bettas can cohabit both in the wild and in tanks. When two female bettas share a tank, one usually bullies the other. However, four or more females generally establish a hierarchy, allowing them to live peacefully. Nevertheless, when females live in communities, hobbyists tend to monitor the aggressive females.
Compatible Fish of Other Species: Hobbyists often put bettas in tanks with other species, typically after careful research and preparation of a back-up plan. Common tankmates include platies (moons), corydoras catfish, and loaches. Females can also be housed with danios, tetras, barbs, and gouramis. Shrimp are popular tankmates because, provided with sufficient natural plant cover, they keep the tank clean without causing bettas stress.
Incompatible Fish of Other Species: Hobbyists usually do not house certain popular fish species with bettas:
Bettas sometimes kill very small fish.
Bettas nip at the fins of fish, e.g. fancy guppies, except when they are about the size as the betta and have unattractive fins.
Mollies tend to nip at their fins and have been known to kill Bettas
Conversely, schooling fish, particularly barbs (and even some tetras) may nip the fins of bettas.
Aggressive fish such as barbs, piranhas, or bluegills obviously cannot cohabit with bettas.
Gouramis such as the dwarf gourami and pygmy gourami may be attacked by male bettas due to their similar appearance.
Paradise Fish, which closely resemble bettas, may attack and kill the male bettas due to their large finnage, particulary the aggressive, territorial males, which can grow much larger than a betta and would have an easy time killing one.
Small fish under 1 inch may be consumed. For example; a 2.5 inch male betta may eat a young neon tetra.
Large male gouramis such as blue gouramis may intimidate and attack male bettas, however this is unlikely.
Male bettas may fight with male gouramis and paradise fish and may even attempt to court and breed with the females. If a fight occurs with a large gourami or paradise fish the betta may be killed. Fights with gouramis are unlikely, but fights with paradise fish are common if the two species are kept together.
Goldfish are unsuitable tankmates, due to their large appetites, preference for low temperatures and high waste excretion. Bettas like many tropical fish may harass small, slow moving fancy goldfish and can even kill them.

http://en.wikipedia.org/wiki/Siamese_fighting_fish