Asian Arowana Care Guide - Size, Habitat & Breeding Notes

The Asian Arowana is a large, powerful freshwater fish with an elongated body, metallic scales and prominent barbels at the tip of its lower jaw. Several naturally occurring colour forms are recognised, including red, golden and green varieties, although their appearance can vary considerably between populations.

This species is an active surface hunter with a distinctive swimming style. Its upturned mouth is adapted for taking prey from or just beneath the water’s surface, and it can leap impressively when startled or pursuing food.

Asian Arowanas are generally solitary and strongly territorial, particularly as they mature. They may become accustomed to a keeper and recognise activity around the aquarium, but their size, strength and predatory instincts make them very different from typical community fish.

In the wild, they inhabit calm, often heavily vegetated waters that expand and contract with seasonal flooding. Habitat loss, collection and trade have placed substantial pressure on wild populations, and the species is classified as Endangered by the IUCN.

Asian Arowanas are native to freshwater habitats in Southeast Asia, including parts of Indonesia, Malaysia, Thailand and Cambodia. Their natural populations are associated with slow-moving rivers, peat swamps, floodplain lakes and forest wetlands.

An adult Asian Arowana requires a purpose-built aquarium or indoor pond of at least 2,000 litres, with considerably more space preferable for long-term welfare. The system should be at least 240 cm long and 90 cm wide, with a secure, reinforced cover because this powerful species is an exceptional jumper. Use strong filtration, efficient aeration and stable water conditions, leaving ample open swimming space; smooth sand or fine rounded gravel and sturdy, securely anchored decor are safer than sharp ornaments. A large, mature specimen may ultimately require a custom pond-sized installation rather than a conventional aquarium.

Up to about 90 cm (35 in) in total length. Females are often broader-bodied and may grow slightly larger than males, although individual size varies.

Asian Arowanas are carnivorous predators. A varied diet can include appropriately sized fish, prawns, mussels, insects and other meaty foods, with high-quality formulated carnivore pellets used where accepted. Food must be responsibly sourced and free from pesticides, disease and sharp bones; feeder fish should not be relied upon as the sole diet.

Asian Arowanas are best kept alone because adults are territorial predators capable of swallowing or seriously injuring smaller tankmates. In exceptionally large, professionally managed systems, robust surface and midwater fish such as large datnoids, mature bichirs, giant gouramis or certain large catfish may sometimes be considered, but compatibility is never guaranteed. Small fish, shrimp, peaceful community species and fin-nipping tankmates are unsuitable, and mixing multiple Asian Arowanas commonly results in severe aggression.

Asian Arowanas are mouthbrooders, with the male carrying the fertilised eggs and developing young in his mouth for several weeks. Courtship and spawning require exceptionally large breeding facilities, excellent water quality and carefully matched adult fish. Breeding is uncommon in home aquariums, and any possession, sale or movement of this species must comply with applicable conservation laws and CITES regulations.

Mature females are commonly deeper-bodied and somewhat larger, while males may have a slightly slimmer profile and a larger-looking head or mouth associated with mouthbrooding. These differences are subtle, and reliable sexing is difficult without observing breeding behaviour or using specialist examination.