Possible Causes of Tumors in Goldfish and Treatment Methods

Possible Causes of Tumors in Goldfish and Treatment Methods

There are two main possible causes of tumors in goldfish. The first is parasitic infection, and the second is known to occur due to low water temperature or poor water quality. Proper water quality management, nutritionally balanced feeding, and minimizing stress are key measures for preventing tumors in goldfish.

If tumors develop, treatment such as water quality improvement and medicated baths become necessary. This article summarizes the possible diseases that can cause tumors in goldfish, their respective treatment methods, and preventive measures.


Diseases that Can Cause Tumors in Goldfish

“Anchor Worm Disease” Caused by Parasites

Anchor worm disease, where small tumors appear on the body or fins of goldfish, is caused by parasites. This disease is more likely to occur in goldfish with weakened immune systems due to poor water quality or stress.

When infected with anchor worm disease, goldfish may experience loss of appetite or reduced activity, becoming immobile. Without early detection and appropriate treatment, it can lead to death.

Pox Disease

Pox disease is a condition where white tumors or spots appear on the skin of goldfish.


It often occurs at low water temperatures, particularly during winter. There is no direct treatment for this disease, and it requires improving the environment to promote natural healing. Pox disease is considered to have low infectivity to other goldfish, but for infected goldfish to recover, it is necessary to provide a comfortable water temperature and quality.

Causes of Tumors in Goldfish

Environmental Issues such as Poor Water Quality or Low Water Temperature

If the goldfish’s living environment is inadequate, it can lead to the development of tumors. Particularly, poor water quality and low water temperature can weaken the immune system of goldfish, making them more susceptible to diseases. Regular water changes and maintaining an appropriate water temperature are necessary to maintain health.

Weakened Immune System due to Nutritional Deficiency

Nutritional deficiency is also a factor that can weaken the immune system of goldfish. Providing a balanced diet can help maintain the immune system and reduce the risk of diseases.

Impact of Overfeeding

Conversely, overfeeding can deteriorate water quality and cause stress to goldfish. It is important to strive for appropriate feeding quantities and proper water quality management.

Stress from Water Quality or Fighting

Poor water quality and bullying by other fish can also be significant stressors for goldfish. Stress can weaken the immune system and potentially lead to diseases. Providing an appropriate living environment is essential for maintaining health.

Treatment Methods for Tumors in Goldfish

Improve Water Quality through Water Changes

If tumors develop, start by improving the water quality. Regular water changes are effective for treating and preventing diseases. Clean water is a fundamental condition for goldfish to regain their health.

Switch to Nutritionally Balanced Food

Changing to nutritionally balanced food is also important in treatment. To enhance the immune system and build resistance against diseases, it is crucial to choose high-quality food.

Remove Parasites through Medicated Baths

If tumors are caused by parasites, medicated baths are effective. If anchor worms (parasites) are visible, they need to be removed using tweezers. In larger environments such as ponds, use Tropical N or Resbermin to target the entire area for medicated baths.

Tropical N and Resbermin are not effective against adult parasites, so after removing the parasites from specific goldfish, use Elbaiju Ace or Kanpara D to promote recovery.

Reduce Stress and Heal Injuries with Salt Baths

Salt baths are useful for reducing stress and promoting the healing of external injuries in goldfish. Prepare salt water with a concentration of 0.5% salt per liter. Conducting salt baths for 3 to 7 days can help restore the immune system and heal wounds.

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