Cotton Wool Disease

Columnaris (Flexibacter columnaris) or Cotton Wool Disease is another bacterial infection. The common name comes from the white tufts that develop around the mouth and spread to the body and fins, often leading to ulcers and a thin appearance.

Often mistaken for a fungal infection because of its mold-like lesions, Columnaris is a common bacterial infection in cultured fish, particularly livebearing fish and catfish. Its name is derived from columnar shaped bacteria, which are present in virtually all pond environments.

The bacteria are most likely to infect fish that have been stressed by such conditions as poor water quality, inadequate diet, or handling and shipping. Columnaris can enter the fish through the gills, mouth, or via small wounds on the skin. The disease is highly contagious and may be spread through contaminated nets, specimen containers, and even food.

Treatment with anti bacterial medicine is usually effective.

More Koi Diseases

Anchor Worm

Crustacean parasite, Lernaea - Anchor worm is a common parasite on our Koi which is clearly visible to the naked eye and can reach 10 to 12mm. The parasite burrows its head into the Koi's tissue, under...(click on product image for more details)

Costia

Costia is a minute Flagellate with 3-4 flagella. It affects both the skin and gills of Koi, and reproduces itself by binary fission. Infestations of this parasite can appear very rapidly indeed, and Koi...(click on product image for more details)

Dropsy

Raised scales rather like a pine cone and eyes standing out from the head. Dropsy itself is not a disease, but rather a result of some other cause. Dropsy is a term given to the swelling that occurs...(click on product image for more details)

Finrot and Ulcers

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Fish Lice -Argulus

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Gill Maggots

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Saprolegnia Fungus

One of the most common fungal infections of Koi. The fungal spores will grow anywhere on the Koi, including the gills, initially germinating on dead tissue. Their threadlike hyphae release digestive...(click on product image for more details)

Skin and Gill Flukes

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Trichodina

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White Spot -Ich

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