What causes gummy fish

Fin rot

Fin rot definition and symptoms

Fin rot occurs mainly in guppies, fighting fish, discus fish and goldfish. White areas are visible on the fins of the fish. The extremely painful disease spreads from the tip of the fin towards the base of the fin. The base of the fin is red and inflamed. The whitish areas fray more and more. Holes form in the fins. Swimming movements appear hectic and restless. Eventually the fins will fall off completely. The bacterial inflammation affects the body. The fish rub against objects in the aquarium or sit in a corner. They appear apathetic and do not eat.

Summary of the main symptoms

  • The fins are frayed, faded and full of holes
  • The fish rub against objects
  • The fish sit on the bottom of the aquarium
  • little food is consumed


Foot and fin rot is caused by bacteria, pseudomonads and aeromonads. If the immune system of the fish is weakened by overstocking, stress, inferior food or poor hygiene, these bacteria multiply strongly and cause inflammation. The inflamed tissue of the fins dies. Fin rot can occur together with other diseases such as fish tuberculosis or fungal infections.


Runs the fin rot acute, the inflammatory processes spread rapidly. The fish die within a few days.

Runs the fin rot chronic, most fish can be cured with the use of medication. The tissue regenerates quickly. If the fins have fallen off completely and the fin base is damaged, healing is no longer possible. After the base of the fin dies and the body of the fish has become infected with bacteria, the fins can no longer grow back.

Fin rot is a factor disease. It cannot be transmitted from fish to fish, and there is no infection.


The earlier a treatment is carried out, the greater the chances of recovery. All fish in the aquarium must always be treated, even if they are not showing any symptoms.

Secretion of sick fish

Fish should be placed in a quarantine tank at the first symptoms to protect them from attacks by other fish. The secretion facilitates drug therapy.

Reduction of stress factors

  • Improving water hygiene
  • no overstocking
  • high quality lining
  • optimal water temperature
  • lower nitrite levels in the water that are too high
  • Increase the oxygen content of the water


The use of medication helps to reduce the bacterial pathogens. Ultimate success can only be achieved by changing the housing conditions at the same time.
Liquid drugs such as JBL Ektol Fluid or eSHa 2000 not only kill germs. They promote the healing of the affected areas and reduce stress. The additional administration of vitamin preparations supports the immune system.

After treatment with medication, the aquarium filters must be replaced or cleaned with activated carbon. Depending on the manufacturer, it may be necessary to replace the water.

Please note that Aquaristik-online.de treats all information without guarantee and has no guarantee of correctness. Furthermore, online information does not replace a visit to the specialist or veterinarian. If you have any questions about fish diseases, their treatments or the use of medication, we recommend that you consult a veterinarian.