Disease library

Fish disease library

Every disease, parasite, and infection in our knowledge base. Tap the keywords to narrow the list — the page updates with a clean, shareable URL.

16 conditions

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Freshwater Tropical

Hole-in-the-Head Disease (Hexamita)

Parasite (flagellated protozoan) disease of aquarium fish. Key signs: pinhole-sized pits on head that enlarge into cavities; lesions…

Moderate

Marine / Saltwater

Marine Ich (Cryptocaryon irritans)

Parasite (ciliate protozoan) disease of aquarium fish. Key signs: white spots (larger and more diffuse than freshwater ich),…

Moderate

Freshwater Tropical

Columnaris (Cotton-Wool Disease)

Bacterium disease of aquarium fish. Key signs: white-grey saddle-shaped lesion across back, frayed fins, mouth fungus-like white patches,…

Severe