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.

11 conditions

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Goldfish

Parasitic Diseases in Koi & Goldfish

Parasitic infestations represent one of the most diverse disease categories in ornamental fish keeping. From the microscopic ciliate…

Mild To To To Severe

Freshwater Tropical

Columnaris

A highly contagious bacterial infection (Flavobacterium columnare) presenting as white/grey patches, often on the mouth, fins, or gills.…

Severe

Freshwater Tropical

Velvet (Oodinium)

Dinoflagellate parasite producing a fine, gold-dust coating across the body. More lethal than ich; gill infection causes rapid…

Severe

Freshwater Tropical

Streptococcosis

Bacterium disease of aquarium fish. Key signs: exophthalmia (often unilateral, 'pop-eye'), corneal opacity, spinning/spiral swimming, darkening, hemorrhages around…

Severe

Freshwater Tropical

Costia (Ichthyobodo)

Parasite (flagellated protozoan) disease of aquarium fish. Key signs: blue-grey film of mucus over skin ('slime disease'), peeling…

Moderate

Goldfish

Anchor Worm (Lernaea)

Parasite (copepod crustacean) disease of aquarium fish. Key signs: greenish-white thread-like worms protruding from skin (the female parasite…

Moderate

Freshwater Tropical

Enteric Redmouth Disease (ERM)

Bacterium disease of aquarium fish. Key signs: subcutaneous hemorrhages around mouth and throat (the 'red mouth'), darkening, exophthalmia,…

Severe

Freshwater Tropical

Enteric Septicemia of Catfish (ESC)

Bacterium disease of aquarium fish. Key signs: acute septicaemic: lethargy, head-up vertical floating, petechial hemorrhages on chin and…

Severe

Freshwater Tropical

Furunculosis

Bacterium disease of aquarium fish. Key signs: acute: rapid mortality without obvious external signs; chronic: characteristic 'furuncles' —…

Severe