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koi diseases diagnosis and treatment you need to know

fice lice koi fish diseases

koi diseases diagnosis and treatment

koi disease how to identify koi fish disease, symptoms, diagnosis and what are the koi fish diseases treatments recognize koi diseases and recommended treatments


koi fish diseases pictures
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koi diseases


koi fish diseases should be identified immediately Regular koi pond maintenance and water-quality

checks help keep diseases away from fish, but illnesses still occur, even in the best-kept ponds.

The first sign of a problem may be a koi fish floating at the surface, by which time it is probably too late for effective treatment.

For this reason, it is vital to set up a routine for examining fish; feeding time provides an ideal opportunity to check their appearance and behavior.


identify treat (koi fish disease) Environmental problems

koi fish diseases
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The health of pond fish is hugely influenced by environmental conditions.

During spells of hot weather, for example, evaporation can significantly lower water levels,

which has the effect of concentrating dissolved nitrogenous waste.

At the same time, elevated temperatures drive oxygen out of the water;

the combination of nitrate and oxygen stress can be fatal, especially for larger fish.

Many of these problems can be avoided simply by topping off water levels regularly during the summer, and incorporating a pump and filter;

these improve water quality, break down waste, and increase oxygen content by creating water movement.

Overstocking a pond, especially if it is not well established, places great stress on its occupants,

and koi fish may succumb to usually benign bacteria that are present naturally in the water.

Overfeeding is another common environmental problem, especially in temperate areas in the spring and fall;

uneaten food decomposes in the water, encouraging populations of pathogens.


Dealing with koi fish diseases
Disease-causing bacteria, fungi, and parasites may be introduced into the koi pond whenever it is stocked with koi fish or plants.

Undesirable organisms can also be brought in on the bodies of animals, especially wading birds, that move from Koi pond to koi pond.These can multiply and cause serious harm

Bloat, or dropsy, is a serious condition, often caused by a fungal or bacterial infection.

Isolate affected fish as a precaution, but this does not normally prove highly infectious

koi fish diseases
Bloat, or dropsy

Fin rot begins in the inter-fin ray membranes, but spreads down the fins until it reaches the body, when it can be fatal.

In extreme cases, rotten parts of fins may need to be cut off under anesthesia.

fin rot koi fish diseases identify treat (koi fish disease)
Fin Rot

Fish lice are crustacean parasites that feed on fish blood. They are obvious when attached to the body, but also live free in the water for up to two weeks.

koi fish diseases
Fice Lice

koi fish diseases

before their presence is detected, and eliminating them can be very difficult.

A table of the most common conditions seen in pond fish, as well as treatment strategies.

If your fish are affected, you are most likely to first notice changes in their behavior and feeding patterns;

a sick fish may, for example, distance itself from others, or take refuge from a plant.

If a disease is suspected, affected fish should immediately be removed from the koi pond and kept in isolation, preferably in a large aquarium.

Here you can inspect the body close-up and check for symptoms of disease or parasite infestation.

Fish lice will be visible in this environment, and you should also be able to detect gill flukes much earlier than would be possible in a pond

.Treatments can be carried out in the tank itself, or in smaller baths, and the fish’s progress can be readily monitored before reintroduction to the pond

If a fish is affected with a disease or parasite, check other fish to determine whether there is a general problem in the koi pond or the disease is an isolated instance.

Look out, too, for secondary infections. Sometimes the entire pond needs treatment with commercial chemicals, but often it is sufficient to treat individual fish.

Check all water-quality parameters before reintroducing the fish; minimizing environmental stress will help prevent recurrence of the condition.

Certain diseases, such as the rapidly spreading koi herpesvirus (KHV), are untreatable,

emphasizing the importance of isolating new fish before introducing them to a pond  and seeking professional advice if many fish become ill.



koi fish diseases
koi fish diseases


Reference Encyclopedia of Aquarium and Pond Fish D Alderton DK, 2008

Swollen cheeks

koi diseases Swollen cheeks
About one-month old fry are apt to be affected by Myxospridea.

Just after they start eating koi food

The gills open wide and show red swollen gill filaments

The diseased koi fish breaths agonizingly and die.

The disease spreads rapidly and many koi fry dies.

If the disease heals, the jaws of the affected koi fry will be deformed.

Koi fish older than two years old are not affected by it because they are immune against it.

The cause is Myxospridea. No medicine is can treat it.

For prevention, the water of the koi pond should be disinfected with malachite green


Raised scales

raised scales koi diseases

The liquid stays under the scales and pushes them up.

The scales bristle up.

The liquid stays also in the abdomen and the body swells

The diseased koi looks like a pine cone.

First, a part of the body is affected, but gradually the disease spreads all over the body

Eyes of the diseased koi protrude.

It breathes hard, swimming around in a crazy manner

After a day or two, the koi fish dies, overturning on its back

The Doitsu happens to be affected by the disease, but it recovers easily

Its cause is supposed to be some bacteria,

an interruption in the blood circulation caused by a diseased blood vessel or internal organ.

Some medicines and excessive eating of live foods

It occurs often in the spring when oxidized pupae are given to koi

When the water temperature is high, it scarcely breaks out.

Any koi fish, either koi fry or adult koi fish, is affected in dirty water.

Sulfa drugs, antibiotics, and furan drugs are efficacious

It is also helpful to break blisters and apply monafracin with Dipterex to the part.

It is important to find the koi diseases in its early stage, otherwise, it will be difficult to cure it.


White Spot koi diseases

white spot koi diseases

Small white spots appear all over the body.

They increase gradually and the body seems to be covered with white powder.

The extreme case is that the outer layer of the skin comes off and the diseased koi fish grows weak to death.

It’s germ is Ichthyophthirius, about 0.7 millimeter long, egg-shaped.

Treatment for the ich koi diseases is a medicated bath of franese for seven days


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