Arowanas were the oldest fish species for over 160 million years, from the late Triassic period about 230 million years ago until the end of the Cretaceous period 65 million years ago. Arowanas are freshwater bony fish. In this family of fishes, the head is bony and the elongate body is covered by large, heavy scales, with a mosaic pattern of canals. The dorsal and the anal fins have soft rays and are long based, while the pectoral and ventral fins are small. Arowana have toothed bone on the floor of the mouth, the tongue equipped with teeth that bite against teeth on the roof of the mouth. The fish can obtain oxygen from air by sucking it into the swim bladder, which is lined with capillaries like lung tissue.

Arownas are carnivorous, often being specialized surface feeders. They are excellent jumpers it has been reported that species have been seen leaping more than 2 metres from the water surface to pick off insects and birds from overhanging branches. Arowanas have been rumored to capture prey as large as low flying bats and small birds. All species are large, and the arapaima is one of the world’s largest freshwater fish, at 2.5 metres in length. Arowana typically grow to around 30cm.

Arowanas species exhibit extensive parental care. They build nests and protect the young after they hatch. Some species are mouth brooders, the parents holding sometimes hundreds of eggs in their mouths. The young may make several tentative trips outside the parent’s mouth to investigate the surroundings before leaving permanently. Arowanas tend to merge in groups of five to eight any fewer may show an excess of dominance and aggression.

For the Chinese and those of related cultures, the dragon is a symbol of good luck and prosperity. In the eyes of the Chinese, the dragon fish has the appearance and majesty of the Chinese Dragon, especially the large scales and barbels.

Arowanas are also used for feng shui to bring good luck. As per the feng shui belief Arowanas are believed to possess capabilities to distinguish between Enemy and a well-wisher. It is believed that if the Arowanas fish in aquarium shows aggressiveness the visitor to house is an enemy and if the fish remains calm the visitor should be a well-wisher.

Several distinct, naturally occurring colour varieties are recognised, each found in a specific geographic region.

The green is the most common variety, found in Vietnam, Myanmar, Thailand, Cambodia, and Malaysia.

The silver Asian is considered part of the green variety by some. It has two subvarieties, the “grey tail silver” or “Pinoh arowana,” and the “yellow tail silver,” each found in a different part of the island of Borneo in Indonesia.

The red-tailed golden is found in northern Sumatra, Indonesia. Mature red-tailed golden arowanas have brilliant metallic gold lateral scales, bellies, gills cover and pectoral and pelvic fin membranes, although the back is dark. In juveniles the areas destined to develop golden colour start out metallic silver

The gold crossback, blue Malayan, or Bukit Merah blue is native to the state of Pahang and Bukit Merah area in Perak, Malaysia.

The red, super red, blood red, or chili redis known only from the upper part of the Kapuas River in western Borneo, Indonesia.