Koi Fish Illness

It is a toss up to what poses the greatest threat to your Koi pond. If predators are in first place, illness will rank a very close second.

All types of fish are subject to getting sick, just like all forms of life. Despite the fact that the Koi fish is a relatively sturdy fish, as are all carp, they are still susceptible to a wide variety of problems. Knowing what these are and how to recognize them is the first step toward their prevention and cure. The most important fact to recognize is that stress is a contributing factor to most Koi pond fish sickness.

When you speak of stress in fish, it has a different meaning than when you speak of it as a human condition. It is not so much that the fish are worried, but it does mean that something is out of harmony in their environment. Many of the factors that cause stress in the fish are environmental in nature. This would include high levels of ammonia or low levels of oxygen. Dirty or contaminated water could be a contributing factor to stress.

Other conditions causing stress are more easily controlled. Excessive handling of fish causes stress as does over crowding in the pond. Even such factors as two many sharp edges in the interior of the pond could be a factor. Stress in this case will be the result of injury to the fish from contact with the edges. Parasites and bacteria will take advantage of the wound to infect the fish. So, stress can be defined within the world of the Koi pond as any condition that encourages the spread of disease.

The major illness causing agents are bacterial, viral, fungal, and parasitic. With only one or two exceptions, all bacterial infections are secondary to stress factors. Bacterial infections can be treated with antibiotics. Viral infections cause nodular growths on the fish and there is no real treatment except to scrape them off and hope for the best. Fungal infections are almost always the result of a secondary problem at the site of a previous injury. Fungus can also attack Koi fish eggs. Parasites, such as the well known Ich, are also possible.

Almost all fish carry some parasites, but they usually have build up some degree of resistance to them. Of course, in the presence of stress, this resistance is lowered and the fish become more susceptible. It cannot be stressed enough that the less stress your Koi are exposed to, the less chance they will become sick.

Aazdak Alisimo writes about water garden [http://www.koipondwatergarden.com] issues for KoiPondWaterGarden.com.