A lot of fish lover encounter their beloved fish sick and I’m sure many among us definitely were frustrated on curing their beloved fish and how to prevent from getting the disease. Here some tips on how to spot fish diseases that infected your fish and what fish treatment you should use for curing them. You can get information about how to prevent fish diseases that appear in your home aquarium.

Ich Disease

Ich Disease

Ich Disease

Ich is easy to notice because of the white spot appear on its gills, body and fins. It cause irritation and inflammation on the body of the fish and the fish start to gyrate against the side tank. This disease happen due to poor water quality, overcrowded in the aquarium and a sudden change of water temperature.
The best medication for treating the goldfish is using Malachite Green, Formalin or Chopper. Do not use the medication together in high temperature because it will reduce the oxygen level of the water and caused respiration problems. The combination of less oxygen level and respiration problem Ich can be fatal.

The best prevention to this disease is quarantine new fish for at least 2 week, don’t overstock the aquarium, fed the fish with healthy food and maintain good quality of water and perform water changes regularly.

Costia Disease

Costia Disease

Costia Disease ( Second Stage of Costia Disease and the body of the fish cover by Mucus all over its body)

The sign and symptom of this disease will show slimy patches around the body of the goldfish and gill, gasping on surface of water and awkward swimming position of the fish. This is a disease cause cloudiness of the skin by protozoan disease and it could be fatal within days. As to treat the fish, raise the water temperature and dips a few salt in the aquarium to prove the effectiveness of the treatment.

Respectively, using QuickCure or Proform C will also work effectively to treat Costia disease. Perform 40% water change with de-chlorinator during the treatment for the goldfish is advisable. As for the prevention method, quarantine new fish or plants for preventing infestation from parasite.

Anchor Worm Disease

Anchor Worm on gill

Anchor Worm

Anchor worm is a parasite disease and is visible on the fish body. The anchor worm dig a hole on the fish body for lay its eggs and die. The body of the fish will become infected because of the hole on the fish body.

The infection cause from new added fish is carrying the parasites and plant carry the larvae on it. As the best treatment for this anchor worm is to clean up entire tank by adding 2mg of potassium permanganate to every liter of water. Treating the fish by removing the anchor worm on its body by using tweezers, and dip the fish in the water with potassium permanganate 100mg/ 2.5gallon water for 25 minute.

After 25 minute, remove the fish to clean water. Respectively, using Anchor away or dimilin medicine helps to treat the infected fish. The best prevention is quarantine new fish and new plant before adding into the goldfish tank.

Cloudy Eye Disease

Cloudy Eye diseases

Cloudy Eye disease

Cloudy eye is a disease of eye disease and cause by different variety such as poor nutrition, bad water quality and rough handling. Cloudy eye can also come from other ailments such as bacterial infection, Ich, Velvet and fish tuberculosis. The symptom of this disease shows cloudy opaqueness on the entire surface of the fish eye.

The best treatment for cloudy eye is perform  40% water changes and keep the pH level to 7 without ammonia and nitrites. Fed the fish with healthy and fresh food that contain high vitamin, mineral and fiber. The prevention method is the same as the treatment.

Cotton Wool Disease

Cotton Wool Diseases on goldfish

Cotton Wool Diseases on goldfish

The name speak for it, a white strands grow on the body, fin and mouth of the fish. This is a fungal infection that present in an aquarium and feed by dead organic matter. This disease can come from different ailments such as previous infection, parasites, rough handling, physical injury, or sudden change of water temperature.

Pimafix for treating fungal infection

Pimafix for treating fungal infection


A recommended treatment for this cotton wool diseases using Malachite Green or Jungle fungus. The best prevention method is maintain high quality of water and temperature, remove uneaten food or any dead organic matter and perform regular water changes.

Dropsy Diseases

Dropsy Diseases

Dropsy Disease

The body of the fish show swollen abdomen due to build of fluid in its stomach. The scales of the fish will become raised and one or both eye will become protruded. The fish eventually stop feeding and the temperature of the fish will raise up.

This disease can cause by poor water quality and often of bacterial infection to the fish. Curing the fish is not easy and it can cause fatal to the fish if it is not treated correctly. As to treat the infected fish, test the water quality and perform water changes to get the perfect quality of water.

Reduce the temperature of the water to 13ºC – 15ºC in next few days. Premix the water into ¼ warm water, add 1 teaspoon of Epson salts for 10 gallons of water tank, and ¼ teaspoon of baking soda for 10 gallon of water. Boosting the immune system of the goldfish, treat it with aloe and garlic treatments.  The best prevention method is keeping the best water quality for the fish.

Finrot Disease

Fin Rot Goldfish

Fin Rot Disease

This disease is one of the easiest disease to notice because it’s infected the fin of the fish. The fin will show split and ragged with white edge on the fin. This is a bacterial infection that cause the goldfish ill if left untreated and also infect the other goldfish in the same tank.

Overcrowded and poor water quality is the cause of causing the fish ill. Clean up the fish tank and perform water changes is the best treatment to cure this disease. On the 1st day, do an immediate 40% of water change and check the aquarium conditions.


API Melafix

Premix 1 tablespoon of salt for 10 gallon water and 1 teaspoon of Epson salt for 10 gallon water. Add half teaspoon of melafix for 10 gallon water if the pH level is not over 7.5. After mixing the ingredients, combine ¼ cup warm water with salt until dissolve and mix it with melafix to dilute in freshwater bucket.

After mixing the melafix in the freshwater bucket, slowly replace 5% fresh water for every 15 minute to preventing the fish shock. Ammonia and chlorine must be remove by adding water treatment into the fish tank. Repeat the process until the 5th day by performing 20% of water changes.

Adding 1 teaspoon of salt for 10 gallon water and mix it until dilute before adding into the fish tank.The 6th day, reverse the treatment and perform water changes for another 5 days.Repeat the entire treatment by using salt on the 11th day. Monitor the fish for 30 days and repeat the entire treatment again if the infection is remain.

The best prevention for finrot is to maintain good water quality and keep the fresh healthy food with small amounts.

Flukes Disease

Flukes infection on gill

Microscope showing Flukes infection on the fish gill

This is parasite disease that look like a flatworms with the size of 1mm. It’s come with a hook around it mouth and usual infest around the gill or body of the fish. The fish start swimming around in the fish tank with a small lump in red or black color beneath the fish skin.

Flukes infected the fish due to new infected fish and plant. The entire fish in the tank will infected by Flukes and may cause the next generation of fish that live in the fish tank. The best treatment is using Fluketabs, QuickCure, Formalin, Potassium Permanganate, and Health Guard to treat fukes disease.

The treatment need to repeat for killing the eggs and larvae of the Fukes disease. If the fish is untreated it could cause fatal to the fish due to gill infection. The best prevention method is to quarantine new fish and plant for 4 week to prevent infection of Flukes disease.

Lice Disease

Fish Lice Diseases ( Argulus)

Fish Lice Diseases

Lice is a fish largest parasite come with the size of 5mm and can be seen in naked eye. Lice usually seen in the fish protected area such as behind the fin, beside the eye and gills. The infection of this Lice disease is caused by un-quarantined new infected fish and plant is added into the aquarium. Curing this disease to the infected goldfish by using holding the goldfish in a damp cloth and remove the Lice using tweezers and taut the red or black spots using neospirin.

The fish need to treat by Dimilin because Lice will lay eggs and the new born will search for a host to live in. The best prevention is to quarantine new fish and plant in a different fish tank and monitor for 2 weeks. Make sure the all the fish is healthy before buying a new fish from the pet store.

Velvet Disease

Velvet Disease

Velvet Disease

This is a parasite disease that known as Rust or Gold disease. The fish give a dusty and slimly look that caused by tiny parasite known as Oodinium. The life cycle of this disease pretty similar to Ich disease. The main cause of this disease are caused by un-quarantine new goldfish.

This disease can also cause fatal to the fish and spread by contaminated tanks, fish, net and testing supplies. The fish will show the symptom of such as clamped fins, the fish loss of appetite, rusty color of skin, the fish start to scratch on hard object and skins of the fish starting to peal off during advance stages.

Treating this velvet disease is similar to Ich disease. The best medication for treating this disease is using Malachite Green, Formalin and Copper Sulfate. Treat the fish tank for 3 days after the parasite was last seen and raise the water temperature. Preventing this disease to the fish, quarantine new fish for at least 2 week and fed them with healthy food. Maintain the quality of the water and stable temperature for the fish to live in.

Swim Bladder Disease

Swim Bladder Disease

Swim Bladder Disease

Swim bladder disease is one of the common disease mostly for goldfish and other species of fresh water fish. This diseases is easy to notice and to treat either by knowing the cause of the disease. There’s a few caused lead to this disease such as poor diet, cause by other diseases, genetic factors and external factors. The symptom of this disease will show the fish having problem to swim, flip over, floating upside down, and unable to swim down and move from bottom.

The best treatment for this disease is to feed the goldfish with peas and beans for 3 days. The food must be steamed, de-skinned and mushed to feed the fish. After that, don’t feed the goldfish for 3 days for allows the gas in it body to pass through. Feed the fish veggies and fruit gradually and the fish will swim normally after a week.

Preventing this disease, pet lover must ensure the quality of water in the aquarium, don’t overfeed the fish and feed the fish with healthy food.


Ulcer disease

Ulcer disease

The cause of ulcer on the body of the fish cause by poor water quality, parasite and infection of wound of the fish. The ulcer is caused by bacterial or fungal infection and minor scratch in poor water quality. The goldfish will show pink and white of an open wounded on it body of the fish.

As for treating this disease, perform 40% water changes and de-chlorinate the newly added water. Treat it with Malachite Green or Acriflavine in the water against the bacteria. Anaesthetize the fish and apply antiseptic on the infected area of the fish. After applying antiseptic, maintain the water temperature in 21ºC during the treatment.

Preventing this disease, make sure the goldfish isn’t injured and keep the attention on other diseases. Last but not least, maintain high quality of water in the aquarium for the goldfish.



Content Inspires by the following resource

  1. https://puregoldfish.com/17-diseases-and-treatments/
  2. http://goldfish2care4.com/goldfish-diseases/anchor-worm.html
  3. http://goldfish2care4.com/goldfish-diseases/clowdy-eye.html
  4. http://goldfish2care4.com/goldfish-diseases/costia.html
  5. http://goldfish2care4.com/goldfish-diseases/cotton-wool.html
  6. http://goldfish2care4.com/goldfish-diseases/dropsy.html
  7. http://goldfish2care4.com/goldfish-diseases/finrot.html
  8. http://goldfish2care4.com/goldfish-diseases/flukes.html
  9. http://goldfish2care4.com/goldfish-diseases/hole-in-the-head.html
  10. http://goldfish2care4.com/goldfish-diseases/ich.html
  11. http://goldfish2care4.com/goldfish-diseases/lice.html
  12. http://goldfish2care4.com/goldfish-diseases/swim-bladder-disorder.html
  13. http://goldfish2care4.com/goldfish-diseases/ulcers.html
  14. http://goldfish2care4.com/goldfish-diseases/velvet.html
  15. http://goldfish2care4.com/goldfish-diseases.html
  16. https://www.youtube.com/watch?v=GyoSh3oNDpc
  17. https://www.youtube.com/watch?v=258nJ3z6xNc
  18. https://www.pinterest.com/pin/276056652135888402/
  19. http://pentairaes.com/proform-c.html
  20. https://www.pinterest.com/?show_error=true
  21. https://www.pinterest.com/pin/6403624453748346/
  22. https://www.pinterest.com/pin/419819996490155087/
  23. https://www.youtube.com/watch?v=r6aCCRwZ-SM