The tiger barb can grow to about 7 centimeters long and 3 centimeters wide, although they are often smaller when kept in captivity. Native fish are silver to brownish yellow with four vertical black stripes and red fins and snout.
It has been reported that the tiger barb was found in clear or turbid shallow waters of moderately flowing streams. It lives in a tropical climate and prefers water with a 6.0–8.0 pH, a water hardness of 5–19 dGH, and a temperature range of 68–79 °F (20–26 °C). Its discovery in swamp lakes that are subject to great changes in water level suggests a wide tolerance to water quality fluctuations. Its average lifespan is 6 years.
In the aquarium
A school of green tiger barbs in a 20 gallon tank.The tiger barb is an active schooling fish that is usually kept in groups of five or more. They are often aggressive in numbers less than 5 and are known fin nippers. If you only keep two in a tank, one will eventually chase the other. Semi-aggressive fish, they form a pecking order in the pack which they may extend to other fish, giving them a reputation for nipping at the fins of other fish, especially if they are wounded or injured. They are thus not recommended for tanks with slower, more peaceful fishes such as bettas, gouramis, angelfish and others with long flowing fins. They do however work well with many fast moving fish such as danios, platys and most catfish. When in large enough groups, however, they tend to spend most of their time chasing each other and leave other species of fish alone. They dwell primarily at the water's mid-level. If you have a clown loach in the aquarium, its similar looks to the tiger barb may cause the tiger barb to try to school with the loach. Tiger barbs do best in soft, slightly acidic water. The tank should be well-lit with ample vegetation, about two-thirds of the tank space. These barbs are omnivorous and will consume processed foods such as flakes and crisps as well as live foods.
P. tetrazona that is close to sexual maturityThe tiger barb usually attains sexual maturity at a body length of 20 to 30 millimeters (0.8 to 1.2 inches) in total length, or at approximately six to seven weeks of age. The females are larger with a rounder belly and a mainly black dorsal fin while the males have a bright, red nose with a distinct red line above the black on their dorsal fin. The egg-layers tend to spawn several hundred eggs in the early morning in clumps of plants. On average, 300 eggs can be expected from each spawn in a mature broodstock population, although the number of eggs released will increase with the maturity and size of the fish. Spawned eggs are adhesive, negatively buoyant in freshwater and average 1.18 ± 0.05 mm in diameter.
Tiger barbs have been documented to spawn as many as 500 eggs per female. With proper conditioning, females can spawn at approximately two week intervals.
Once spawning is finished, they will usually eat any of the eggs that they find. It is usually necessary to separate the fish from the eggs after spawning in order to prevent the eggs from being eaten.