Ammonia Poisoning

Definition

Ammonia poisoning is the damage to fish gills + nervous system caused by detectable ammonia in aquarium water (above 0.25 ppm). The single fastest aquarium killer.

Practical use

Symptoms: gasping at surface, lethargy, red gills, sudden death. Test ammonia weekly; any reading >0 = problem. Fix: 50% water change + Seachem Prime to detoxify ammonia for 24 hours while bio-filter recovers.

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