An Introduction to Koi Fish Diseases
Keeping your koi fish healthy can be expensive and difficult if you have no knowledge of what you’re doing. Doing some background research and learning about the different diseases that can effect the happiness and health of your koi is the first step.
Anchor Worm Disease is a parasitic worm disease caused by anchor worms or what they call "Lernaea". The disease can leave the host with ulcer once it leaves the body. It also causes the koi to begin scraping its body against objects and leaving inflamed spots on the skin. The Anchor worm disease is highly contagious and must be dealt with quickly as these parasites can penetrate the skin of the koi.
Chilodonella is another parasitic disease that is of major danger to a koi's health even if it is just one parasite. The Chilodonella is treacherous because it has a vast range in tolerating temperature and attacks the koi fish at low temperatures when they are unable to resist. These parasites are also very small that in early stages of its existence, no owner may be able to see symptoms of it.
Cotton Wool Disease is a type of bacterial infection caused by the bacterium called Flexibacter and its name is derived from the white stuff that develops surrounding the mouth and then spreads to the body and the fins, which will eventually lead to ulcers and can even thin the koi fish in appearance.
Fish Lice, also known as Argulus, is one of the few parasites that are visible to the naked eye. It can be recognized by its green, circular shape, and moves around the fish. Owners can easily notice this as the koi fish begins to scratch and rub against objects and red, inflamed spots on the gills and the body begin to appear.
Gill Flukes are small, very common fish parasites that grow up to 2mm. These parasites do not cause much harm, but when in big groups, these gill flukes can cause real damage to a koi fish's health. Aside from causing lesions and tissue damages to the koi, they can also produce side effects, like hyperplasia and weaken the koi's immune system.
These diseases are some of the worst any koi fish could develop and even pass on to other fish. Once any symptom appears, immediate treatment must be practiced so not to endanger the health of the other fish.