A list of common diseases and infections encountered
by Goldfish is given below.
If you find your Goldfish rubbing itself against anything in its
tank, it probably has anchor worms. An anchor worm is a white
stick-like structure that hooks itself onto the fish. You will notice a
red ring at the point of attachment.
Fins held close to body, especially in liverbearing fish.
Fish bloated with scales standing out. Fish resembles a pine cone.
TAIL, FIN OR MOUTH ROT
Flesh eaten away around mouth, tail or fin. Possible redness at the base area.
ANCHORWORM AND EXTERNAL PARASITES
Thread-like worm hanging from fish. Base of anchor worm may be red. Nodules or reddish pimples on skin may be seen.
White or grey cottony growth or patch on any part of the fish.
Gills hang partly open and may pump fast. Gills may appear red.
Red streaks on fins or body with no sign of skin damage.
White, sugar-like crystals on fins or body of fish.
Following ammonia surges, black spots might appear on the back
and sides of your Goldfish.These spots should disappear within
two weeks and its place should be replaced by fresh orange
Gills hang partly open
and may pump fast.
Gills may appear red.
If you notice excessive slime coat, isolation,
clamped fins, scratching, sores and ulcers, your fish
is probably suffering from flukes. If your fish has
gill flukes you will find it gasping for air on the
surface of the water. Usually Potassium
Permanganate, Droncit, Fluketabs and Formalin are used to treat
flukes. You will have to continue with the treatment a little after
all symptoms have subsided as sometimes fluke eggs and larvae
may be left behind and if not killed they will attack your fish
This disease is caused normally after your fish has suffered aninjury. Parasites attack the wound and this disease can soon spread
to other healthy fish. This disease can cause some serious damage
like severely affecting the gills.
The symptoms of this disease include clamped fins and breathing
problems. The fish will become lethargic and spend a lot of time at
the bottom of the tank. Sometimes, a whitish blue pigment cov ers
their body. Treating this can be tricky and it's best for you to get
help from a vet or from the pet store from which you bought the
Your fish's fins will look clamped if the water in
which it is housed is of poor quality. The presence
of parasites in the water also causes this condition.
If this occurs, get the water checked for the level of
ammonia, pH and nitrites.
Fins held chose to
body, especially in
Most goldfish suffer from constipation at least once in their lives.
They don't have the strongest digestive system. If you feel thatyour fish is constipated, feed it peas which acts as a mild laxative.
If you find your fish's scales sticking out, it is
probably due to dropsy. This is a bacterial
infection that normally kills fish.
Dropsy is not a specific disease, but rather a condition where the
fish's abdomen becomes swollen. It causes concentration of the
fluids in the body tissues or cavities. This results in swelling of the
fish's abdomen, thus creating a pinecone effect.
The scales protrude from the body. A sudden swelling of the
abdomen (scales may stick out) is known as acute dropsy while a
slow swelling of the abdomen is known as chronic dropsy. The
actual cause of this swelling could be one of several conditions:
Acute Dropsy - Internal bacterial infection can cause internal
bleeding and thus cause acute dropsy.
Chronic Dropsy - cancer: In this case, the abdomen is slow to swell
as the cancer affects the fish's internal organs. If the fish is not
isolated in the early stages of the disease, it could spread to otherfish that are being housed with the ill fish.
Chronic Dropsy - parasites: Internal parasites can cause
dropsy(abdominal swelling) because they are rather large parasites
or because of the damage they are causing with the fish's organs.
The abdomen tends to swell over a period of time if the fish is
infested with internal parasites. It is best to isolate the sick fish at
once to help maintain the outbreak of disease with other fish!
Goldfish are said to be somewhat more prone to dropsy than
other fish. In some cases it is caused by a Costia Infection. Be
careful when making this decision. Some fish could be spawning
Symptoms: The body will have a general swelling with protrusion
of scales. The eyes may even bulge.
Dropsy is not very contagious. The earlier it is caught
the more likely treatment will be helpful. It is best to up the water
temp to about 82-86 degrees and use epsom salts (1/8 teaspoon of
epsom salts per 5 gallons) instead of aquarium salts because they
will help the fish to lose some of the fluid that has built up. (It is
common to think that salts would help, but in reality the fish isbloating and having a hard time ridding its body of fluid; whereas
the epsom salts will "draw out toxins"). It is also wise to increase aeration since the
temps will be higher. Water quality is very important at this time.
This will have to be tried for about 2 weeks. Now if you think
the fish is suffering from parasites you will need to treat for them
This salt grain-like looking parasite affects most fish.
The Ichtyopthirius attaches itself to the body of the
fish and feeds off the Goldfish. They fall to the
bottom of the tank in a couple of days where they
lay eggs and the cycle continues. This can sometimes
kill your fish if not treated thoroughly and rapidly.
Fin rot occurs when your goldfish has injured itself and bacteria
grow on the wound. You will notice a whitish colouring on the
edge of the fins. If not treat quickly, this will lead to a fungainfection.
Leeches are worm-like parasites that feed on blood. There are
around 300 species of leech that attack fish. The wound caused by
the leech's suckers could sometimes get fungal and bacterial
infections. If affected by leeches, your fish will rub itself against
the tank. A 3% salt dip will take care of the leeches. Don't try
pulling out the leeches without the salt dip as this will injure your
fish. There are medicines available at pet stores as well.
Fish lice are greenish disk shaped creature that is about a fifth of
an inch in length. You will notice your fish rubbing itself against
the tank walls when affected by these lice. The places in which the
lice attach themselves turn red. You can pluck
these out manually from your fish. You have to do
this quickly as they reproduce very fast.
There are many types of fungi and can be brokendown into different categories. The most common is a bacterial
infection that forms white cotton-like patches. If you notice this,
be sure to take your fish to a vet immediately.
Sometimes a small hole appears on the fish's body that later
develop into tubular eruptions with cream-colored or yellow
strings of mucus. If you notice this, you should put the fish in a
separate tank and take it to a vet.
If you find out fish's eyes popping out, it is the first sign of
dropsy. You can prevent the occurrence of this deadly disease
with medicines. Pop eye can affect pond and aquarium fishes. The progress of the
disease depends on what is or has caused it. Bulging eyes can result
from a number of causes, including fish tuberculosis,
ichthyosporidium, dropsy, and bacterial infections.
One or both eyes protrude abnormally. (remember
some fish are bred to have protruding eyes ex: fancy goldfish)Treatment: Use anti-parasite and anti-bacterial treatments
If you find you fish losing scales for no apparent reason, you
should immediately change the water and treat the tank for all
This is another disease caused by parasites and if not treated in
time, it could kill your fish.The symptoms of this disease include
frayed fins, sluggishness, loss in coloration and damaged gills.
Treatment of this disease is a two-step process. One, you will have
to treat your fish with medicines and two, you will have to
thoroughly clean the tank.