My goldfish has a growth on its fin. Is it a fungal infection?

If it is fuzzy, it is likely fungal. You can try with a commercial antifungal medication such as API Fungal Cure, methylene blue or Pimafix/Melafix. These can be purchased online or in the aquarium section of most pet stores. Read package directions carefully and remove the carbon insert from the filter before treatment if indicated. Plain aquarium salt (NOT table salt) can be used in conjunction with one of the above treatments to aid healing. Dissolve up to one tablespoon per gallon of water into the tank. Fungal infections can take up to two weeks to resolve with treatment. Maintain proper water parameters (0 ppm ammonia/nitrites, 40ppm or less nitrates and temp of 65 F to 72 F). If possible, remove the affected fish yo a hospital tank during treatment.

Goldfish are susceptible to fibroma tumors (benign) and sarcoma cancers (malignant). I cannot tell you what they are exactly just by looking at the photos. As long as they do not bother the fish (interfere with movement, bleed nor cause discomfort), most people leave them alone.

Hi and thanks for your request and pictures. This tumor like lesion could be due to a lymphocystis. This is a virus (herpes), mostly seen in goldfish, which can cause these type of cauliflowers mass-like lesions. Of course to be confirmed, this should be sampled and or removed completely. Unfortunately these masses can grow much bigger that the one showed in the pics and can become infected. A clinical examination at your local veterinarian is essential to confirm these clinical suspicions and treat appropriately. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further. If this answer was helpful please let us know, this will be used to improve our service!

It may be a bacterial infection or trauma. Monitor for bullying since you have other fish. Most minor infections can be managed or resolved by maintaining pristine water quality. A bit of plain aquarium salt (NOT table or Epsom salt) can be used as a general tonic to aid in recovery, reduce stress and improve gill function. Dissolve 1 tablespoon per 5 gallons of water in a cup or two of tank water and gently pour it into the tank. Treat for 10-14 days then reassess the condition. If the condition is unchanged, consider a broad spectrum antibiotic. You can find one in the aquarium section of the local Petco. Follow label directions carefully and remove the carbon filter insert during treatment if indicated.

Thanks for reaching out about your aquarium and including photos. Did you test your water quality prior to the water change? Continue to test for pH, ammonia, nitrites and nitrates. Pristine water quality is needed for health. Are any of the fish new, that could have introduced parasites? Itching/flashing can be due to water quality, external parasites, bacterial or viral infections and other causes. The white lesions on the photo could be fungal infections. A skin scrape and examination under the microscope (at a veterinarian's office) is needed for an attempt to determine a cause. Fungal infections are often secondary problems, so check water quality first. Good luck.

This could be bacterial or parasitic infection. It is difficult to determine definitively since the image provided is not clear. Fish can be difficult to photograph. Basic care includes checking water quality and chemistry. This can be done using a home test kit or by submitting a water sample for testing. The local Petco may do this for free or for a small fee. There should be an absence of ammonia and nitrites with nitrates at 20-60 ppm. pH should be as close to 7 as possible, avoiding large swings. Koi can tolerate a wide range in temperature, but generally do best between 65 F and 75 F. Again, avoid large swings in temperature to prevent stress or shock. If necessary, a partial water change can be done to stabilize chemistry and/or improve water quality. If you have other koi, consider placing this one in a hospital tank to make treatment easier and to prevent spread if the condition is infectious. Plain aquarium salt (NOT table or Epsom salt) can be used to reduce stress, improve gill function, treat minor infection and aid in recovery. Dissolve 1 tablespoon per 5 gallons of water in a cup or two of tank water and gently pour it into the tank. Treat for 14 days then reassess the condition. If there is no change, consider a broad spectrum antibiotic or "all in one" treatment. Either can be found in the Aquarium section at Petco. Follow label directions carefully and remove the carbon filter insert during treatment if indicated. All that said, if the spots multiply and appear like tiny grains of salt, it could be an ich infection. In this case the entire tank will require treatment. There are several commercial ich medications that can be used. You will also need to thoroughly vacuum the substrate/gravel in the tank and wipe down all tank furniture.

It looks like it may be some sort of fungal infection on Tiller. I would recommend to the the photo to a pet store and see if they agree. They can also sell you fungal medication to add to his water. Sometimes these infections can be serious. If you have a pet store in town that specializes in fish, they are your best reference. Best of luck!