Skin and Gill Flukes

Gill and Skin flukes are two of the family of monogenetic trematode genera, all of which are characterised by the large grappling hooks which are used to attach themselves to their victims.

Flukes are another common parasite affecting our koi are both egg layers and live bearers. They range from 0.05 to 3.00mm long and there are actually a huge number of species in the genus.

Affected Koi often exhibit classic signs of irritation and flash, jump or rub themselves against objects in the pond in an attempt to rid themselves of their attackers.
Flukes are not visible with the naked eye. When viewed under a microscope, the parasites are clearly visible as nearly transparent and worm like, and the hooks are clearly visible.

Flukes are a bit like fleas on dogs and cats and it is common to see one or two on a slide as a healthy Koi can control parasite numbers and their mucus helps prevent the parasite moving. Treatment is therefore only necessary if flukes are seen in numbers.

Chemical control of both types of fluke can be achieved with Chloramine T, Malachite Green, Formalin, or Potassium Permanganate. In order to kill all generations, repeat treatments may be necessary, the frequency being dependent on temperature and chemical used.

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)

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...(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

A number of bacteria are associated with finrot, lesions and internal hemorrhaging, notably Aeromonas and Pseudomonas. Ulcers usually start at the site of an injury, the bacteria then infect it causing...(click on product image for more details)

Fish Lice -Argulus

Argulus another crustacean parasite, round and up to 1cm wide. They have a sucker to hold on to the Koi with needle-like mouth parts which they stick into the Koi and inject a toxin. This causes intense...(click on product image for more details)

Gill Maggots

Gill maggots are the mature females of the parasitic crustacean Ergasilus. Ergasilus gill maggots will appear as grayish black and white parasites several millimeters long infesting the...(click on product image for more details)

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)

Trichodina

Trichodina is one of the easiest protozoan parasites to detect under the microscope as it is almost perfectly round with hundreds of hooks which resemble cilia found its periphery and it constantly...(click on product image for more details)

White Spot -Ich

Caused by Ichthyopthirius multifiliis. The white spots on the skin, gills and fins are individual protozoan cells that are under the skin and feed on the body fluids and cells. They then punch out of...(click on product image for more details)