Normal Flaring (Display)
Brief flare during feeding, at new tank mates, or when seeing reflection. Lasts 5-30 seconds. Fish returns to normal swimming.
Adult males flare during territorial disputes. If tank is solo, flaring at reflection is common — tape black paper on one side to stop.
Aggressive Flaring
Prolonged flaring (minutes) with body curved sideways = aggression. Target of aggression will shelter or dart away.
In multi-arowana tanks, this is a warning sign. If not resolved within a few days, separate the dominant fish.
Distress Flaring
Constant gill flaring + rapid breathing + surface gulping = oxygen shortage or gill parasites.
Test ammonia (should be 0), nitrite (0), and oxygen (>5 ppm). Add aeration and check for flukes with microscope.
Parasite-Related Flaring
Gill flukes cause intermittent flaring + rubbing on decor + mucus patches on body. Diagnose with microscope scrape if available.
Treatment: praziquantel at 2mg/L for 3 days, repeat after 10 days. API General Cure works for mild cases.