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.

13 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

Freshwater Tropical

Mycobacteriosis (Fish Tuberculosis)

A slow, chronic infection caused by Mycobacterium spp. Symptoms include emaciation, spinal deformity, and granulomas. Zoonotic risk —…

Critical

Freshwater Tropical

Fin Rot

Progressive deterioration of fin tissue caused by opportunistic bacteria — usually a symptom of poor water quality.

Mild

Freshwater Tropical

Dropsy

Bloated body with pinecone-stuck-out scales — a symptom of organ failure, not a disease itself. Prognosis is generally…

Critical

Freshwater Tropical

Cloudy Eye

Hazy or opaque film over one or both eyes — usually a sign of bacterial infection or chronic…

Moderate

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

Bacterial Cold Water Disease

Bacterium disease of aquarium fish. Key signs: rtfs in fry: spiral swimming, exophthalmia, dark colouration, anaemia, splenomegaly; older…

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

Freshwater Tropical

Edwardsiellosis

Bacterium disease of aquarium fish. Key signs: gas-filled abscesses in muscle ('emphysematous putrefactive' lesions), ascites, exophthalmia, foul odour…

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

Bacterial Kidney Disease (BKD)

Bacterium disease of aquarium fish. Key signs: chronic, progressive: granulomatous lesions in kidney (creamy white nodules), spleen, and…

Moderate