Arowana Care Guide 2025: Build a Thriving Aquarium Home 🐠🌿

By Dr Duncan Houston BVSc 🩺

💬 Arowanas are majestic, ancient "dragonfish" that can live 10–20 years and reach up to 4 ft in captivity. But their beauty comes with big responsibilities. This detailed 2025 vet-backed guide covers everything: tank setup, water quality, diet, behavior, tankmates, and health monitoring so your arowana can flourish. 🧩

🔹 1. Understanding the Arowana

Arowanas (family Osteoglossidae) include Silver, Asian, and Gold varieties. Silver arowanas (Osteoglossum bicirrhosum) grow to 3–4 ft over 10–20 years :contentReference[oaicite:3]{index=3}. They need large, secure tanks—minimum 300 gal per adult :contentReference[oaicite:4]{index=4}.

Key traits:

• Surface feeders with a tendency to jump—secure lids essential :contentReference[oaicite:5]{index=5}.
• Ancient lineage dating back to the Cretaceous, recognized by their bony tongues and large scales :contentReference[oaicite:6]{index=6}.
• In the wild, fish slowly swim through blackwater habitats—your setup should replicate that environment :contentReference[oaicite:7]{index=7}.

🏠 2. Tank Size & Setup

Arowanas need horizontal space and quality water:

• Tank size: At least 300 gal, ideally 400–500 gal, length ≥ 6 ft :contentReference[oaicite:8]{index=8}.
• Shape: Wide, not tall—these fish are surface swimmers :contentReference[oaicite:9]{index=9}.
• Cover: Heavy lid or plexiglass barrier to prevent escape :contentReference[oaicite:10]{index=10}.
• Substrate & decor: Use fine sand or smooth gravel; minimal driftwood or flat rocks to prevent injuries :contentReference[oaicite:11]{index=11}.

💧 3. Water Parameters & Filtration

Keeping water clean is critical:

• Temperature: 75–86 °F (25–30 °C) :contentReference[oaicite:12]{index=12}.
• pH: Neutral to slightly acidic (6.5–7.5) :contentReference[oaicite:13]{index=13}.
• Hardness: Soft to moderate; adjust with RO or distilled water if needed :contentReference[oaicite:14]{index=14}.
• Filtration: Strong canister/heavy filtration with moderate flow—turnover at least 4× tank volume/hr :contentReference[oaicite:15]{index=15}.
• Aeration: Use air pumps or surface agitation to ensure oxygenation :contentReference[oaicite:16]{index=16}.

♻️ 4. Maintenance Schedule

Arowanas produce significant waste—stay on top of cleaning:

• Weekly: 20–30% water change, clean substrate with gravel vacuum :contentReference[oaicite:17]{index=17}.
• Monthly: 40% change if filtration is suboptimal :contentReference[oaicite:18]{index=18}.
• Cage & filter: Scrub walls, rinse filter media monthly.
• Parameter checks: Weekly tests for ammonia, nitrites, nitrates, pH, hardness, and temp.

🍽️ 5. Diet & Nutrition

Carnivorous arowanas require a varied, protein-rich diet:

• Base diet: Floating carnivore pellets to engage natural feeding habits :contentReference[oaicite:19]{index=19}.
• Supplements: Shrimp, krill, worms, small fish, insects; avoid live feeder fish unless quarantined :contentReference[oaicite:20]{index=20}.
• Frequency: Juveniles 2–3× daily; adults 1× daily or every other day :contentReference[oaicite:21]{index=21}.
• Feeding tip: Provide floating foods or use surface décor to prevent “droopy eye” :contentReference[oaicite:22]{index=22}.

🤝 6. Behavior & Tankmates

Arowanas are intelligent but territorial:

• Temperament: Preference for solitude after juvenile stage :contentReference[oaicite:23]{index=23}.
• Tankmates: Suitable companions include large peaceful fish (e.g. big catfish, pacu, oscars) :contentReference[oaicite:24]{index=24}.
• Avoid: Fish small enough to be eaten or aggressive species.

🔍 7. Common Health Concerns

• Water-related stress: High ammonia/nitrates can cause gill issues—test regularly.
• Jump trauma: Hitting tank lids can injure the head/eyes—lid needed.
• Eye droop: Corrected by feeding off-surface :contentReference[oaicite:25]{index=25}.
• Parasites: Use quarantined or frozen foods to reduce risk; treat appropriately if needed.
• Swim bladder issues: Prevented with varied diet and stable water parameters.

📅 8. Long-Term Care & Lifespan

With proper care, arowanas thrive for decades:

• Longevity: 10–20 years :contentReference[oaicite:26]{index=26}.
• Slow growth: They grow slowly—mature size reached around 3–4 years.
• Breeding: Arowanas are mouthbrooders; sexual maturity occurs at 3–4 years :contentReference[oaicite:27]{index=27}.

💡 9. Tips for Success

• Lock tank lids securely and dim bright lighting.
• Quarantine new fish or food items before introducing them.
• Flip tank décor seasonally to mimic natural environments.
• Keep log of water quality, feeding, growth, and health status.
• Consult a fish veterinarian if signs of illness appear (e.g. lethargy, financial).

📲 Final Thoughts from Dr Duncan

Arowanas are stunning yet demanding aquarium stars. They require careful attention to tank size, water quality, nutrition, and behavior. With a secure environment and proper maintenance, you’ll enjoy decades of beauty and companionship from these living dragons. 🐉

Need help troubleshooting water issues, nutrition plans, or health concerns? Visit AskAVet.com and download the Ask A Vet app. Our fish-savvy team is available 24/7 to support your arowana journey. 📱