|Picture to right shows a fish suffering
Swollen abdomen and raised scales, giving the body a pine cone
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.
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.
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 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
There are many treatments available.
Treatment should be repeated in order to kill each batch of cysts
as they burst releasing free swimming ciliates.
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.
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.