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Related Articles & Questions
- Care Sheets
Essential Large Marine Fish Care Guide: Tank Setup, Diet, & Tank Mates
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- Health & Wellness
Why are my fish still sick after velvet treatment, and tank has algae?
Thanks for reaching out. Have you tested water quality for pH, ammonia, nitrite and nitrate. Correct problems. Don't see any signs of external lesion on the pictures, except fine erosion, and possible gravid fish. A veterinary visit is probably needed to trouble shoot for disease. Randomly adding chemicals to the water could have detrimental effects. Good luck.
Updated on September 24th, 2025
- Health & Wellness
What are the best medicines for fish parasites, bacteria, or fungus?
Pimafix is an acceptable "natural" antifungal treatment. Melafix is for bacterial infections. Kanamycin, erythromycin or metronidazole are good broad spectrum antibiotics. Fungus Cure (by API) is an excellent antifungal. You can find these medications in the aquarium section of most pet stores or even online. Follow label directions carefully and remove the carbon filter insert during treatment if indicated. The cornerstone of any treatment is to first maintain pristine water quality and stable chemistry.
Updated on September 24th, 2025
- Health & Wellness
Why are my koi losing scales and goldfish have white head bumps?
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.
Updated on September 24th, 2025
- Health & Wellness
My fish has an internal infection from an injury. What should I do?
Thanks for reaching out about Candoris and including photos. A veterinary visit is recommended as systemic antibiotics needed. Medications added to the water are not absorbed systemically and will not help with internal infections and will likely affect the biological filter. Check and correct water quality as pristine conditions needed to heal. Adding 1 gram non-iodized salt (aquariums salt) per 1 Liter, to decrease stress and osmotic load on the fish. Good luck.
Updated on September 24th, 2025
- Health & Wellness
Why are my goldfish sick with fin rot and not improving after water changes?
Hi, and thanks for your question. This is a quite concerning presentation and it is likely to be related to water quality. Begin by submitting a water sample for quality testing. Most pet stores will do this for free or a nominal fee. Clinical examination should always include a water quality check, even if you have done so already. Water testing should be performed with a quality test kit, measuring NH4, NO2 and NO3. High ammonia levels, PH imbalances may be responsible for these signs. Oxygen concentration and quality of the filters should be determined as well. If water quality is good and there are no major imbalances, your fish should get examined to look for any sign of bacterial/fungal infection and eventually water should be treated. 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!
Updated on September 24th, 2025
