Arowana Care Guide: Tank Size, Diet and Legality in Singapore
The Asian arowana holds an almost mythical status in Singapore — prized for its symbolism, beauty, and the sheer presence it commands in any room. Yet keeping one demands serious commitment in space, budget, and legal compliance. This arowana care guide Singapore legality overview from Gensou Aquascaping Singapore, built on over 20 years of hands-on experience at 5 Everton Park, lays out everything you need to know before taking the plunge with Scleropages formosus.
Legal Requirements in Singapore
Asian arowanas are CITES Appendix I listed, meaning international trade is restricted to captive-bred specimens with microchip certification. In Singapore, you may legally purchase and keep captive-bred Asian arowanas — but every fish must come with a CITES certificate and embedded PIT tag (microchip). Buying from unlicensed sellers or importing without documentation is a criminal offence under the Endangered Species Act.
South American arowanas (Osteoglossum bicirrhosum) — the silver arowana — carry fewer restrictions and are significantly cheaper, though they grow just as large. African arowanas (Heterotis niloticus) are occasionally available but rarely kept in Singapore.
Tank Size for Adult Arowanas
An adult Asian arowana reaches 60–90 cm. The absolute minimum tank size is 250 cm long by 75 cm wide by 60 cm tall — roughly 1,100 litres. Many serious keepers opt for custom tanks of 300 cm or longer. Silver arowanas, which can exceed 100 cm, need equally generous dimensions.
Weight is a major consideration in Singapore housing. A 1,200-litre setup weighs approximately 1,400 kg fully loaded. HDB flats on upper floors have a live load rating of around 150 kg per square metre — a large arowana tank may exceed this unless positioned against a load-bearing wall on the ground floor. Landed homes and ground-floor units are far more practical. Consult a structural engineer before installation.
Water Parameters and Filtration
Arowanas thrive in warm, slightly acidic to neutral water: pH 6.0–7.5, GH 4–12 dGH, temperature 26–30 °C. Singapore’s PUB tap water suits them well after dechloramination. Given the tank volumes involved, a sump filtration system is virtually mandatory — canisters alone cannot handle the bioload of a fish this large.
Weekly 25–30 % water changes maintain nitrate levels. At 1,000-plus litres, that means draining and refilling 250–300 litres per session. A Python water changer connected directly to the tap saves enormous effort. Budget $50–$80 per month for water conditioner, electricity (pumps, lights, potential chiller), and filter media.
Feeding and Diet
Arowanas are surface-oriented predators. Market prawns (shell removed for juveniles, shell on for adults), crickets, mealworms, and superworms form the dietary backbone. Pellet foods such as Hikari Arowana Sticks provide balanced nutrition and are available locally for $20–$40 per pack.
Avoid feeder fish — they carry parasites and disease that can devastate an expensive arowana. Centipedes and frogs, once popular as treats, pose choking and toxin risks. Feed juveniles daily; adults do well on four to five meals per week. Overfeeding leads to drop eye — a condition where the eye rotates downward, widely believed to be linked to a high-fat diet and surface feeding of heavy items.
Common Health Issues
Drop eye is perhaps the most discussed arowana ailment. While genetics play a role, environmental factors — reflections from below, high-fat foods, and small tanks — contribute. Some keepers cover three sides of the tank and float ping-pong balls on the surface to encourage upward gazing, with mixed results.
Gill curl, where the gill plate flares outward, often results from poor water quality or inadequate oxygen levels. Caught early, it may correct with improved husbandry. Severe cases sometimes require surgical trimming by a specialist — a stressful procedure best avoided through prevention.
Tank Mates for Arowanas
Suitable companions must be too large to swallow and not aggressive enough to damage the arowana’s scales. Stingrays (freshwater Potamotrygon species), large bichirs, peacock bass, and clown loaches are common pairings. Avoid anything that competes for the surface zone — two arowanas in one tank invariably leads to dominance fights unless the tank exceeds 400 cm.
Many arowana keepers in Singapore prefer a species-only setup, letting the fish be the undivided star. A clean, well-lit tank with a solid background colour — black or dark blue — showcases the metallic scales beautifully.
Costs and Long-Term Commitment
An entry-level captive-bred Asian arowana starts at around $300–$500 for common colour variants. Premium red or gold crossback specimens fetch $2,000–$10,000 or more. Add the tank ($1,500–$5,000 for custom builds), sump system ($500–$1,500), and ongoing running costs, and arowana keeping is undeniably a premium hobby.
These fish live 15–20 years in captivity. At Gensou Aquascaping, we encourage prospective keepers to plan for the full lifespan — rehoming a large arowana is difficult and stressful for the fish. If the commitment fits your lifestyle and budget, few freshwater species reward dedication as visibly as a mature arowana in peak condition.
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