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.

9 conditions

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Goldfish

White Tail Disease in Koi & Goldfish

White tail disease is a serious and poorly understood condition caused by microsporidian intracellular parasites that destroy muscle…

Moderate To To To Severe

Freshwater Tropical

Hexamita (Hole-in-the-Head)

Intestinal flagellate parasite causing pitted lesions on the head and lateral line, especially in cichlids and discus. Often…

Moderate

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

Lymphocystis Disease

Virus disease of aquarium fish. Key signs: wart-like, cauliflower-shaped, pinkish-white nodules on skin and fins (greatly enlarged virus-infected…

Mild

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

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

Bacterial Kidney Disease (BKD)

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

Moderate