You may notice a difference in the behavior of your koi. It is possible that the fish is suffering from one of several koi fish diseases. Some of these diseases can kill a koi in a very short time. This article will list some of the more common koi fish diseases that will enable you to see the differences, recognize the disease and begin the correct treatment.
ICH:ichthyphthirius multifulis. This disease will manifest itself with white spots on the body of your koi. The disease is the result of fresh water ICH. There are times when a microscope is needed to see the spots. This koi fish disease is due to a faulty immune system. Although large koi may survive, smaller fish will have difficulty fighting the disease and usually die. The disease will attack the gills and kill the fish. The cycle of the disease varies and may be over in 2-5 days or last as long as 5 weeks. By increasing salt and elevating the pumps the disease may be prevented. Excessive salt can also kill your plants. Experienced koi breeders and hobbyists prefer Malachite Green and Formalin 37% as treatment.
CHILODINELLA: lchthyobodo ncatrix or Costia are koi fish diseases that kill large numbers of fish. The owner of the fish does not have much time to discover the disease and fight it. The fish die quickly. If the water is salted properly, the disease is dormant. The fish will exhibit difficulty breathing, sunken eyes and a bluish sheen to their skin are some of the diseases.
TRICHODINA: this parasite is saucer shaped. It causes spider web lesions on the koi skin. Smaller fish will also have gill damage with this kio fish disease. Irritation and scratching is also present. The only side effects of the scratching are ulcerations. Salt will clear it in a day if it is added to your pond water. Properly salted ponds are vital to the health of your koi.
OODINIUM: parasites cause this koi disease. Its common name is velvet disease. Gold colored, velvety dust is found on the fish. This is one of the koi fish diseases that is not helped by salt. Formalin may be added to the water to control the disease.
EPISTYLIS: although an uncommon parasite, it is a dangerous one that can cause koi fish diseases. It is the result of poor water management. If you fail to change your water you could have this parasite appear in the pond. This particular parasite resembles a fungus and lives in ulcers and wounds. There will be white colored tufts in and around the wounds. The parasite can be quickly removed with a change of water and addition of salt.
LERNEA: Beware of lernea. It will live a long time and are a distinct threat to your koi. The life span of this parasite is 14 days. The additions of Fenthion, Trichloffon, Malathion, Dylox and Sald can help to eliminate this particular parasite.
ARGULUS: This parasite is very visible with its invasion. They are green and disc shaped. They attach to the fins and sides of the koi and suck. They easily cause ulcerations. Formalin does not work on Argulus. You will need to use Fenthion and Dimilin, which are Organophosphates.
GYRODACTYLUS: The gyrodactylus lives up to 15 days. They are a cause of severe koi fish diseases. Treatment is formalin 37%, Organophosphates, Droncie, Potassium and Salt. Usually the owners will start with salt first. The other agents should not be added unless the salt does not work.
Dropsey/Bloat: commonly found in fresh water fish, it is the result of an infection in the stomach that is caused by a bacterial invasion. The abdomen will swell. It can be treated with Gentamicin, Amikacin, Azactam, Baytril, Chloramphenicaol.
SCOLIOSIS: a deficiency of vitamin C can cause scoliosis. The best way to prevent scoliosis is by supplying oranges, watermelon and grapes to your fish.
LYMPHOCYSTIS: this is one of the more common koi fish diseases. This is a viral pathogen and is transferred easily and very difficult to treat. If a fish becomes infected, it must be separated from the other fish to avoid spread of the disease. There is no cure for this disease.
CARP POX: this is another of the koi fish diseases that is caused by a viral pathogen. Waxy, soft and wart-like lesions will appear on the fish. This disease also has no cure. Separate the sick fish from the healthy ones.
It is important to be familiar with these common koi fish diseases.