Why Arowana Get Pinecone Disease (Raised Scales) and How to Treat It
📝 Summary
Pinecone disease (also called raised or loose scales) is common in arowana. It can be triggered by large temperature swings, poor water quality, or internal infections such as enteritis and ascites. Mild cases often respond to the 'old three methods' — raise temperature, add salt, and partial water changes — while severe cases need antibiotics.
1 Arowana Pinecone Disease: Causes and Treatment
Causes and Treatment of Arowana Pinecone Disease
Pinecone disease makes the scales stand out all over the body, so the fish looks swollen. The common triggers are:
1. Large Temperature Swings
When the new water you add differs greatly from the old, or seasonal changes cause a big swing, the arowana can’t adapt and its scales flare. This often affects only part of the body. Rapid water changes that create local temperature spikes, or a strong flow that hits the fish directly, can also trigger it when the fish’s immunity is low.
Solution: If only a few scales are raised and the base shows no redness, swelling, discharge, or infection, try raising the temperature. Hold it at 32°C (89.6°F) steadily; the fish may recover the next day. Even after recovery, keep the higher temperature for over a week — don’t drop it the moment the fish looks normal. Lower it slowly, holding each 1°C step for 2–3 days, until back to normal, giving the fish time to adjust and preventing relapse.
2. Enteritis, Ascites, or Internal Organ Infection
Poor water quality easily leads to pinecone disease along with internal bacterial infection, and is far more serious than temperature-induced cases. Old, unchanged filter media and heavily polluted water with long-term nitrate spikes let bacteria attack the internal organs and flare the scales. Also, feeding live food that isn’t cleaned or has its sharp shell removed can scratch the gut lining and cause enteritis or ascites, with scales flaring.
Enteritis or ascites usually show as mild prolapse, a red and swollen vent, a bloated belly, and lethargy (lying at the bottom). Severe cases bring sunken or bulging eyes, faded color, all scales raised, and ulceration or scale loss — a grim sight.
Solution: For internal bacterial infection from poor water, change water and restore quality promptly. For enteritis or ascites, antibiotics such as gentamicin injection may be needed.
In short, act the moment you notice pinecone disease. Early cases often respond well to the ‘old three methods’ — raise the temperature, increase aeration, add a little salt, and do sensible partial water changes. Severe cases need medication too.
To prevent it, keep water quality good, avoid large temperature changes, and maintain a stable temperature.
These are the main causes and treatments of arowana pinecone disease.
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