Hole In The Head Disease (Hexamita): Causes And Treatment

Hole in the head disease, also known as Hexamita or head and lateral line erosion, is an infection of the freshwater fish’s head resulting from an infestation with the parasite Hexamita sp and it’s common among koi and other popular ornamental pond fish.

This parasite enters the fish through wounds in its head and quickly reproduces, damaging tissue and causing disfiguration as it grows larger. If left untreated, this disease can cause serious damage to your fish’s health and even death, so be sure to diagnose a hole in the head disease in your tank immediately if you notice any signs or symptoms.

What is hole in the head disease?

hole in the head disease

Freshwater and saltwater species suffering from hole in the head disease often have small, dark holes or hollow areas around their heads and lateral lines. A few spots may be present, or there may be many. The colors, sizes, and depths may vary, or they may all be the same color.

What causes hole in the head disease?

In most cases, hole in the head disease is caused by stress. Many factors can cause stress in fish, including diet, water quality, aggression, and space. A fish’s reproductive, growth, and immune functions are diminished when a stressor persists in an environment it cannot escape, triggering a chronic stress pathway.

An impaired immune system can allow bacteria on the fish’s skin to cause localized infections once the fish’s defenses are weakened.

Even if there are no external signs of injury, a lateral line erosion or hole in the head can develop when the water temperature drops or rises suddenly.

According to another popular theory, this disease may be caused by mineral or vitamin imbalances. It has been claimed by some aquarists that the use of activated carbon increases the risk of this disease. It is believed that humans may experience a rise in disease incidence due to the removal of some of the beneficial minerals from the water by carbon.

Aquarium Brine Shrimp (Artemia salina)

In addition, an increase in Hexamita organisms in the intestine may lead to mineral imbalances as well as malabsorption and inadequate absorption.

The phenomenon of lateral line erosion occurs most frequently during times of high stocking density, overcrowding, and increased feeding activity. Newly introduced fish into an aquarium environment can also get hole in head disease, especially when they are stressed or overcrowded.

Is Hexamita contagious?

I will not say yes. Hexamita can only be spread to another fish if the one that is carrying it comes into direct contact with another. Hexamita cannot survive without a host, so you shouldn’t be concerned about spreading it throughout your cycled aquarium with solid filtration.

To prevent others from getting sick, quarantine new fish for about two weeks (and possibly longer) if you must add them to a tank with infected ones.

Fish parasites called Hexamita comes in several forms. Fish of any species can develop this disease, but it is more prevalent among aquarium fish due to the presence of an organelle called Oikomonas Hexamita.

Hole in the head fish disease symptoms

hole in the head disease

A typical symptom of this condition is pitting-type lesions along the lateral line and on the head. When the holes become larger, secondary bacterial and fungal infections will develop if the holes are not treated.

The condition may seem mild at first, but if there is no intervention, the holes will become larger and the hole will become larger. A severe infection can develop from these lesions, causing the fish to lose their appetite and eventually die.

Your fish may also be suffering from hole in head disease if they have holes or missing scales around their face or gills. If you don’t treat your fish right away, these holes will get worse as bacteria multiply.

Observers may also find their fish swimming slightly tilted on one side, moving asymmetrically through the gills, or even having a small depression on one side of their head.

Ghost Shrimp (Palaemonetes paludosus)

Aquarium owners may notice lumps on the heads of their fish before Lateral Line Erosion occurs. Based on the distance your fish is from you, these bumps may seem slightly pearly or fleshy.

A fish’s body becomes infected with parasites, resulting in these lumps. Fish with sores on their heads is a good indication that they have an early hole in head disease.

Since hole in the head disease of fish is caused by several factors, treatment usually involves multiple approaches. In addition to eliminating Hexamita, improving water quality and supplementing vitamins and minerals is also necessary.

Can fish recover from hole in head disease?

hole in the head disease

Yes, of course. As long as a veterinarian diagnoses hole in the head disease correctly and treat it early, fish can recover.

A hole in the head disease can be treated by following these steps:

  • With the help of a veterinarian, determine if you have hole in the head disease.
  • Keep infected fish isolated if possible to prevent the spread of the disease.
  • If you have a carbon filter in your tank, remove it. Certain medications may be absorbed by carbon filters and cause harm to your fish.
  • For treating aquatic diseases like hole in the head disease, you may also consider purchasing an ultraviolet light (UV) filter. It generally takes three to five days to complete UV treatments depending on the temperature of the water. However, they are largely harmless and leave no residue in the water after they are completed.
  • Fish may also benefit from water changes during treatment by reducing stress.
    Hole in the head disease treatment

Adding metronidazole to a treatment tank housing infected fish is a common treatment for Hexamita infection. Keeping an eye on the quality of the water is essential, and adjusting it if necessary in order to meet the fish’s exact requirements.

It may be helpful to add fresh or frozen meaty foods such as seaweed strips or lightly steamed broccoli to the diet to improve nutrition. If you are treating a specific species, make sure that the nutrition is tailored to that species.

Vernal Pool Fairy Shrimps (Anostraca)

Oscars, for instance, are carnivorous, while some cichlids are primarily vegetarian. There may be a need for additional antibiotics such as Kanacyn, Maracyn, or Furan in cases of secondary bacterial infections. Treatment should be started as soon as the first symptoms are noticed, whether this is a disease or anything else.

Can humans also get hole in the head disease?

It is possible for fish to carry germs that cause people to become ill, just as it is with all animals. Water, where fish live, may also become contaminated with these germs. People rarely get sick from keeping fish, even though fish and aquarium water can carry germs.

Will salt cure hole in head disease?

In addition to fighting off holes in the head disease, salt can also help fish fight other diseases. It does not treat this disease, however. Fish scales, which are a layer of skin around each fish, will not penetrate salt because they are made of a hydrophilic material.

Salt should not be used in aquariums excessively, or for prolonged periods of time, because you do not want your fishes to be exposed to excessive amounts of salt. During treatments, only a small amount should be added.

Hole in the head disease prevention

Stress reduction is the primary focus of prevention. Fish are more susceptible to this disease and others because of stress, whether it is caused by parasites, poor nutrition, or poor water quality.

It is likely that you will encounter this disease if you own Oscars, cichlids, or discus in your aquarium. Provide optimum water conditions; feed the highest-quality diet, recognize the disease and initiate early treatment. You should not have to worry about your fish developing the disease again if you manage them and maintain them properly.