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.

12 conditions

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Freshwater Tropical

Aeromonas (Ulcer Disease)

Bacterial infection causing open ulcers, hemorrhagic patches, and red sores. The #1 cause of mortality in koi ponds…

Critical

Marine / Saltwater

Marine Ich (Cryptocaryon irritans)

Saltwater white-spot disease. A 2006 resistant strain renders traditional copper and formalin treatments ineffective — quinine sulfate is…

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

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

Ich (White Spot Disease)

Parasite (ciliate protozoan) disease of aquarium fish. Key signs: small pinhead-sized white spots (cysts) on skin and fins;…

Moderate

Freshwater Tropical

Ceratomyxosis

Parasite (myxosporean) disease of aquarium fish. Key signs: distended abdomen, ascites, hemorrhagic enteritis, lethargy, blackened tail, anaemia; chronic…

Critical

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