Asian Arowana

The Asian arowana (Scleropages formosus), known as the dragonfish, is a Southeast Asian blackwater fish of slow-moving forest swamps and wetlands, with colour varieties native to Borneo, Sumatra, the Malay Peninsula and mainland Southeast Asia. It is IUCN Endangered and CITES Appendix I - one of only eight fish species on Appendix I - so international trade is the most restricted category and legal specimens must come from CITES-registered captive-bred stock (microchipped, with certificates). It grows up to 90 cm, males mouthbrood the eggs, and possession is prohibited or permit-restricted in several countries including the United States.

Asian arowanas grow up to 90 cm, so the profile's 60 cm describes a young adult, not the ceiling - plan housing for the larger figure. Sexual maturity comes late, at 3-4 years, and females produce only 30-100 large eggs, which the male mouthbroods. Diet shifts with size: juveniles feed on insects while adults feed on other fish.

Asian arowanas are territorial and normally seen alone or in small groups; in the wild they shelter among Pandanus roots or similar structures by day and feed at night. Keep the tank single-specimen or only with large, similarly sized fish in a very large aquarium, because it is predatory and territorial. Provide solid structure for daytime shelter, and expect surface-oriented, upper-column activity rather than bottom dwelling. Confidence note: medium-confidence guidance drawn from published species care information; treat as conservative guidance, not a precise requirement.

Because they can grow to 90 cm, Asian arowanas require large aquaria - a minimum around 1,000 litres with a long, wide floor - and like all arowanas they need a tight-fitting cover to prevent escape, so the lid is safety equipment, not decoration. They are surface feeders that take food from the upper water column, which is exactly where an uncovered tank loses fish. Keep the water well-filtered, soft, slightly acidic and stable at 24-30 C. Confidence note: medium-confidence guidance drawn from published species care information; treat as conservative guidance, not a precise requirement.

Read the 1,000 L minimum as floor area first: a long, wide box (on the order of 2 x 1 m) rather than a tall column, because this is a surface patroller that needs straight-line swimming length. A 400 L tank can only hit that volume by being narrow, which is the wrong shape for a 60-90 cm fish. Territorial fish also need the length to maintain distance from tankmates and their own reflection. Confidence note: medium-confidence guidance drawn from published species care information; treat as conservative guidance, not a precise requirement.

Carnivorous surface feeder: offer a high-quality meaty diet - shrimp, crickets, mealworms, earthworms, feeder fish and quality pellets - presented at or near the surface, because they prefer to take food in the upper parts of the water column. Adults eat other fish while juveniles eat insects, so scale prey size as the fish grows. Live foods are widely used to enhance colour, but only offer items the arowana can swallow without risk.

House it singly, or only with large tankmates of similar size in a very large aquarium - it is predatory and territorial, and anything smaller than its mouth is potential food. Bottom-dwellers and invertebrates do not get a free pass just because it hunts high in the water column. Any tankmate assessment must be by size, not by temperament labels.

Verdict: a beautiful, expensive and legally complicated fish - CITES Appendix I and IUCN Endangered mean only CITES-registered captive-bred stock (microchipped, with certificates) is legal, and possession is restricted or prohibited in places including the United States, Florida and New Mexico. Husbandry-wise it is an advanced, territorial 60-90 cm predator needing 1,000+ litres, soft acidic well-filtered water and a lid that stays shut. Skip it if you cannot verify legal provenance, if you want a community tank, or if you cannot fund the enclosure it will outgrow.