The common reasons goldfish get sick are if the fish tank is dirty, due to poor filtration, poor water quality and low oxygen levels. This article provide the information of the common goldfish diseases and how to treatment.


Caused by poor water quality or an excessively high pH level and bacterial infection. Also commonly affects newly imported goldfish.

Symptoms: Pinky-white open wounds, often with a white edge and sometimes secondarily infected by fungi and other bacteria.

Treatment: Fish lose salts quickly through open wounds, so add aquarium salt at a dose of 1-3g/litre. Use an antibiotic treatment both short-term antibiotic baths and topical antibiotic. If treatment fails you will consult a vet for advance treatment.


Dropsy is a symptom that the fish is in kidney failure and is not able to excrete enough fluid. Usually caused by bacterial infection. Viral infection, nutritional, metabolic and osmoregulatory problems can also be responsible.

Symptoms: Swelling of the body cavity due to a build-up of fluid. Scales become raised that make the fish look like a pine cone. One or both of the eyes may be protruded.

Treatment: Add aquarium salt at a dose of 1- 3g/litre can help to prevent salt loss. Use a broad spectrum antibiotic treatment is the best option in most cases. A good antibiotic is chloramphenicol and tetracycline.

White spot

Caused by Ichthyophthirius multifiliis parasite infection due to poor or incorrect water conditions, fluctuating temperature and general poor husbandry.

Symptoms: Small white spots on the skin, fins and gills.

Treatment: Treat promptly with an anti-parasite medication such as Metronidazole, malachite green and formalin. It may be necessary to raise the water temperature to 80° F to improve the effectiveness of the treatment.

Bacterial infection

Bacterial infection covers a range of goldfish illnesses, with varying causes. Dirty water and/or cold water, overcrowding and corn-based diets can lead to bacterial infection.

Symptoms: Red and inflamed areas on the body and fins, raised scales, skin ulcers, exophthalmos (pop-eye), dropsy or swollen abdomen, fin rot. Additionally, affected fish may be lethargic and anorexic.

Treatment: Use Short-term baths for a few hours each day using anti-bacterial products such as potassium permanganate or antibiotics. For open sores it is recommended to wash them in iodine or hydrogen peroxide solution and apply antibiotic ointment. Topical treatments can use in minor to moderate cases. Medicated food these are specially prepared foods containing antibiotics. You can prepare your own medicated food by top-dressing ordinary food with an appropriate antibiotic. Antibiotics (injectable) this usually course of five injections over a ten-day period in combination with topical treatments.

Swim bladder disorder

Caused by bacterial infection, incorrect diet, trapped gas, physical deformities, poor water quality. Genetic problems in selectively-bred goldfish. Commonly affects egg-shaped fancy goldfish.

Symptoms: Fish have difficulty swimming to the surface, or to the lower levels of the tank.

Treatment: Change diet and improve water conditions by soaking flake food before feeding so that it will sink lower in the water so the goldfish will not intake as much air and the food will be moister and easily digestible. An increase of vegetable content in the goldfish’s diet may also help their digestive system. Increasing the tank water temperature to 78-80°F and add aquarium salts dose of 1- 3g/litre to the water. If the goldfish condition is not improve a medicated food, or broad spectrum antibiotic can be given.

Leave a Reply