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.

17 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

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

Branchiomycosis (Gill Rot)

Fungus (true fungus) disease of aquarium fish. Key signs: rapid breathing, gasping at surface, gill necrosis with white/marbled…

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

Costia (Ichthyobodo)

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

Moderate

Freshwater Tropical

Trichodina Infestation

Parasite (ciliate protozoan) disease of aquarium fish. Key signs: excessive mucus (slime coat), pale or 'milky' patches on…

Moderate

Freshwater Tropical

Fish Lice (Argulus)

Parasite (branchiuran crustacean) disease of aquarium fish. Key signs: flat, round, 5–10 mm semi-transparent lice visible attached to…

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

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