Why Arowana Scales Turn Black and How to Fix It
📝 Summary
Blackening scales in arowana usually trace back to unstable water (temperature or quality swings), overfeeding loaches, or bacterial infection. Steady the environment, ease off the loach, or run a medicated bath — and use color-enhancing feeds to bring the sheen back.
1 Causes and Fixes
Environment swings: arowana are sensitive to temperature and water quality; big swings or fouled water turn scales black and can cause worse problems. Keep the environment stable — heat as needed to hold 28–30°C and pH 6.5–7.5, change water every 3–5 days at one-third volume, and keep the new-to-old temperature difference within 1–2°C. Improper feeding: too many loaches (a favorite live food) can darken the fish; cut loach and other scale-less fish, and switch to small fish, shrimp, and bloodworms to restore vivid color. Bacterial infection: poor water or an untreated wound can blacken scales; bathe the fish in oxytetracycline, penicillin, or yellow powder once daily for 3–5 days.
2 Keeping Color Vivid
Animal feeds like small fish, shrimp, bloodworms, centipedes, and roaches enhance color; if you can, add small frogs or soft-shell turtles for trace elements. Insects often carry parasites and bacteria, so disinfect them before feeding, and vary the diet to avoid malnutrition. Dedicated arowana or color-enhancing pellets also help.
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