Goldfish Lice Disease | Symptoms, Treatment, Prevention

Lice are a giant goldfish parasite alongside Anchor worms. It is quite easy to spot them moving around shaded areas like eyes, gills, and behind fins. It is essential to treat and get rid of lice in the tank because they can make the fish stressed and uncomfortable while also itching itself.

Goldfish Lice Treatment

Causes Of Lice In Aquarium Tanks

Fish lice are also known as Argulus among aquarists is one of the most developed fish parasites. It is capable of causing enormous harm to the tank members if left untreated. They are capable of producing this great harm because they feed on the flesh and blood of their goldfish host.

They usually attach themselves to gills and skin of goldfish, and they are capable of causing extreme irritation and itching in their goldfish host. Fish lice can cause slightly raised spots on the fish, which is usually green-grey or brownish.

Lice can grow up to 5mm in diameter. They are not microscopic; hence, you can readily see them with your naked eyes. If you are not very careful and observant, you can mistake them for algae or some random tank dirt.

The dominant causes of lice in the goldfish tank are the introduction of random un-quarantined fish into your tank and indiscriminate addition of plants to the tank. Dirty and overcrowded tanks also make it easy for them to establish themselves and spread in the aquarium tank.

Symptoms Of Lice In Goldfish

Lice usually fall off the body of goldfish in about 2 hours, but they must have caused some damage and lay eggs before falling off. Goldfish exhibit specific symptoms when lice eggs or adult lice themselves are present in fish tanks.

The apparent symptoms of lice invasion of goldfish include; stress, discomfort, flicking of fins, irritation, and itching, as well as the loss of appetite and sluggishness. A heavy infestation of goldfish by lice can result in extreme weakness of the fish from blood loss to the point of death.

You can also find your goldfish rubbing its back against the side of the tank and other surfaces. They often exhibit this behavior because they desperately want to get the lice off their body.

How Do You Treat Lice On Goldfish?

The first step in treating lice in the tank is the removal of the visible parasite with tweezers. You should, however, tight the red spots that might result in using Neosporin. This manual removal should be accompanied with follow up treatment with aquarium salt or Dimilin.

The essence of the follow-up treatment is to get rid of lice eggs to eliminate the risk of its continuous existence. Likewise, the follow-up treatment will also prevent fungal and bacterial growth that can result in a disease outbreak in the tank.

How To Identify Fish Lice In The Tank

Lice are very nasty parasites that grip tightly to their goldfish host. Their large size even makes it easier for them to fasten their grip on their host. They also have a long needle-like part that they stick into their host to suck blood.

Apart from the fact that lice themselves suck the blood of goldfish, they are also carriers of many fish diseases. They are easy to identify because of their little green specs. These tiny green specs usually appear like a dot of green algae on fish.

When you take a closer examination of this parasite, you will discover they look like a freaky disc-shaped alien creature with dark eyes. The presence of lice on the skin of goldfish can make them itchy and scratchy. Likewise, its presence on the gills of fish can make it turn pink, and consequently result in breathing difficulty.

Prevention Of Lice In Goldfish

Lice are very contagious and can quickly spread to all members of a tank, especially in overcrowded tanks. It can result in disease in one fish, which can quickly spread to other members of the aquarium tank. Therefore, it is essential to quarantine affected fish for a few days.

You can even prevent lice from entering your tank at all by taking some precautionary and prevention steps. You should quarantine any new fish for about two weeks before introducing it to your tank.  This quarantine is to prevent the fresh fish from adding any parasite to your existing fish collection.

Likewise, you should thoroughly examine any plant you want to introduce to the tank to ensure it is not carrying any parasite. If it is a non-living plant, you can consider sterilizing it before adding it to the tank.

How To Remove Lice From Goldfish Tank

In any case, if lice find its way into your tank one way or the other, you should get rid of it as soon as possible. One can easily classify the treatment of lice in goldfish into two parts; the first part is to manually eliminate adult lice, while the second part is the follow-up part of getting rid of eggs and preventing the growth of bacteria and fungi.

You can easily remove visible lice by using tweezers while holding the goldfish in a damp cloth. You can then tighten the red spots with the use of Neosporin. On the other hand, you can allow the lice to fall off the body of the fish by itself. This falling off usually happens within 2 hours.

remove using tweezers

This removal is then accompanied by follow up treatment. The essence of this follow up procedure is to get rid of lice eggs and to prevent the growth of bacteria and fungi.

The follow-up treatment proceeds by dipping the fish in two teaspoons per gallon of non-iodized salt for a few days. You can also use alternative methods like dabbing the louse with cotton wool that has a 50/50 mixture of kerosene and Turpentine on it.

It would be best if you, however, were careful of not allowing any of this solution to get to the mouth, gills or eyes of the fish.


Lice are macroscopic parasites that affect goldfish. They are dangerous and life-threatening if not quickly curtailed. The physical removal of lice from the body of goldfish is not enough treatment to get rid of the parasite. It is crucial to get rid of lice eggs and prevent the growth of bacteria and fungi with some follow up treatment.