Some fish diseases can be fatal if not treated immediately

  Fish Diseases  
Fish are only like human beings.From time to time they get ill, and/or get various diseases. If', you, take ill you pay a visit to your doctor where he/she would prescribe a treatment that would hopefully cure you. Unfortunately fish are not able to take a stroll to the doctors, so this is where you become the doctor and apply whatever water treatment required.

As long as you adopt a reasonable approach to maintaining your garden pond, the fish should enjoy good health most of the time. Minor ailments may develop occasionally, but many of these will rectify themselves of their own accord.

Fish should be checked on a regular basis.
An ideal time to do this is when you are feeding your fish. Try to cast an eye over each fish, and take notice if all the fish are feeding.
A tell tale sign that something is wrong with a fish, is, it will tend to distance it's self from the others, probably hide behind a plant. If this is the case you should remove the fish from your pond, to an isolation tank, immediately. ( I have a large fish tank set up in my garage, which I use as a hospital tank).
Diagnose the ailment of your fish and treat the fish tank accordingly. Don't forget to treat the pond water as well.

Tetra treatments are very good

There are many remedies available from most aquatic centers or pet shops. Always read the instructions carefully. Under treating the pond water can be just as bad as over treating the pond water.



 Mouth Rot  Whitish growths around the mouth and cheek area resulting in erosion of tissues.
 Fungus  White or creamy-colored fluffy patches on fins and/or body.
 Slime  Grey'ish film on body
 White Spot  Body and fins covered in small white spots.
 Ulcers  Appear on head or body, often as circular round open wounds.
 Fin Rot  Inter-fin ray membrane becomes opaque and then starts to rot.
 Gill Parasites  Inflamed gills, mucus on gills, gill covers may be held open

Above, indicates just a few of the more common diseases you may come across during the years ahead.
Don't panic though, as most of these are easily rectified by adding the appropriate treatments to your pond water.

Tetra treatments are very good












Picture to right shows a fish suffering from Dropsy.
Swollen abdomen and raised scales, giving the body a pine cone appearance.
The fish must be isolated in a separate tank immediately, with the water temperature slightly higher than that of the pond water, give a salt bath or one of the antibacterial treatments.
In an advanced form, it is usually fatal.
Watch for symptoms of Dropsy in the springtime.



Ulcer Disease

Commonly known as "Hole in the side"
The first signs of ulcers are shallow, open sores,usually of a reddish colour,which appear on the body,and sometimes also on the fins.Unless immediate action is taken the disease can spread very quickly to all the other fish in the pond.
The infected fish should be removed from the pond and isolated in your hospital tank.Purchase a suitable treatment from your local aquatic centre or pet shop and treat tank and pond water immediately. I use tetra treatments.



Ulcer disease is primarily caused by pseudomonas and aeromonas bacteria.This bacteria may already be present in the pond in small concentrations,waiting to pounce as soon as conditions are right. These organisms may be introduced to a pond by visiting amphibians, birds, or through new fish which are already diseased, but not to a clinical level.
Ultimately, death may occur.
This is caused by infection, causing loss of body fluid or through widespread infection of the blood (Septicemia).
Ulcers may also be associated with other diseases such as Dropsy, which is also caused by bacteria.


Fin Rot

This is caused by parasitic bacteria. As soon as this is seen on any of your fish it should be treated imediately because if the rot spreads to the body, the koi will die. Initially, the inter-fin ray membrane becomes opaque and then begins to rot which exposes the fin rays that also rot. This will continue on fins and tail until it reaches the body.
If this is allowed to happen the chances are, your fish will almost certainly die.


White Spot

White Spot appears dotted about the body and fins. They are tiny ciliates which swim around looking for a host, if they do not find a host within 48 hours they will die. When they find a host they bury themselves into the dermis where they feed on the body cells. After feeding on the host for about 3 weeks they fall from the fish to the bottom of the pond where they reproduce in cysts.
There are many treatments available.
Treatment should be repeated in order to kill each batch of cysts as they burst releasing free swimming ciliates.


Fungus Disease

White or Cream coloured fluffy patches on the fins and / or body.
Fungus Disease often appears as strands of cottonwool type filaments hanging from the koi. These strands some times have a green appearance which is due to algal growth on the fungus. The probable cause for a fungal infection is when the fish has hurt it's self causing a small open wound, the fungus will feed on the wound and then spread over more and more of the body.
Treatment can be with a mixture of Formalin and Malachite Green, Salt or any of the other fungal compounds available from most Aquatic or Pet shops.


Salt Treatment

The simplest, and yet one of the most effective, cleaning treatments for Koi is a salt bath.

The infected Koi can either be immersed (very short bath) in a very concentrated (saturated) salt solution (10 parts of salt to 90 parts of water) or the infected areas can be painted with the saturated saline solution. In addition it is recommended that an injection of Gentamycin be administered.

With the immersion method, immersion time depends on the size of the Koi and the temperature of the water. Both are critical. If the pond temperature is 25°C (77°F), immersion time for a Koi 30 to 55 cm (12 to 22 in.) is 5 seconds; 6 - 7 seconds for a Koi measuring 55 to 70 cm (22 to 28 in.); 4 seconds for a Koi under 30 cm (12 in.). If the pond temperature is below 20°C (68°F;) you may add 1 second. An alternative is to anesthetize the infected Koi and liberally "paint" the infected area with the saturated salt solution. Then let the treated infected area be exposed to the air for 2 - 3 minutes before returning the Koi to the water. Whilst carrying out this treatment you should keep the remainder of the koi's body covered with a soft towel soaked with pond water. If the disease is bad, repeat the treatment in 5 days. In addition it is necessary to improve the pond water quality. ie: partial water change and clean excess organic debris from filter and pond bottom.

The rule of thumb is always that if the koi appears distressed, remove it immediately, even if you are following the above directions.

Tetra treatments are very good for your fish pond. There are other manufactures
but I tend to stick with what I know.

Diseases in Garden Ponds
 Graph to the left is an indication when you should treat your pond against disease and parasite infection.
Exact commencement dates vary every year according to how early spring and autumn arrive.

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