Goldfish fin rot: separate sick fish or treat the whole tank?

It may be easier (and more economical) to use a one or two gallon vessel to use as a "hospital tank". Use the water from the main tank initially and change the water in the smaller tank every couple days. For the small amount of water, you can use a water conditioner such as Prime (by SeaChem). Find it in your local Petco. A bit of StressCoat will also aid in recovery. Maintain pristine water quality and proper temp (78F to 80F) to aid in healing. Make sure he continues to eat normally as well.

Thanks for reaching out about your fish. This type of erythromycin is not readily absorbed by fish but you are trying to treat a topical infection so might work. Treatment courses usually go for 7-10 days, but water quality must be carefully monitored daily during treatments. How did you determine fin rot? Have you tested water quality for pH, ammonia, nitrites and nitrates? Bacterial additives often affect water quality by affecting the biological filtration. Systemic antibiotics are recommended but require a veterinary visit. Good luck.

Leaving the hospital tank on the floor is fine if that is less stressful for your sick dish. Be sure the top is secured to prevent her from jumping out or other pets from getting in. Survey the area around it for any negative stimuli, such as loud noise, cool drafts or strong vibrations. Make sure the water is sufficiently heated as well. Treat with a combination of a broad spectrum antibiotic and plain aquarium salt (NOT table or Epsom salt). You can find an antibiotic in the aquarium section of the local Petco. Follow label directions carefully and remove the carbon filter insert during treatment if indicated. Dissolve 1 tablespoon of salt 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 Leela's condition. Be sure to maintain pristine water quality and keep her as stress free as possible. If you don't want to medicate, you can try a combination of Pimafix, Melafix and StressCoat or similar conditioner. Follow label directions carefully and maintain clean water and a stress free environment.

This could be a bacterial or fungal infection. If there are other fish in the tank, trauma cannot be ruled out. if there are other fish, ideally Tiny should be removed to a quarantine or hospital tank for treatment. If not, you can treat Tiny in the main tank. First, confirm adequate water quality. You can use a home test kit or submit a water sample for testing. The local Petco may offer water testing for free or for a small fee. Aim for an absence (0ppm) of ammonia and nitrites with nitrates at 20ppm or less. perform partial water changes, no more than 30% total volume at a time, using conditioned and temperature matched water. Goldfish are cold water fish that do best between 68 and 74 F. The filter should be rated for at least twice the volume of the tank. Plain aquarium salt (NOT table salt) can be used to reduce stress, treat minor infection and aid in recovery. Dissolve 1 tablespoon of salt per 5 gallons in a cup or two of two of tank water and gently pour it in. Treat for 10-14 days then perform water changes to reduce salinity. Only treat the amount of water being replaced. More often than not, pristine water quality will allow recovery of minor infections or trauma. If necessary, you can use a broad spectrum antibiotic or all in one product, such as LifeGuard (Tetra) or All In One Remedy (Marineland), to treat the tank. You can find these products in the Aquarium section of the local Petco or online. Follow label directions carefully and remove the carbon filter insert during treatment.

Fin rot is commonly caused by poor water quality. Submit 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 she/he is in a tank larger than 2 gallons move her/him to a smaller tank if possible to make treatment easier. The best treatments for mild fin rot are frequent water changes and aquarium salt. Maintain the water the treatment tank between 76-78'F. Turn the light and filter off for the time being. Aquarium salt can be used at 1 teaspoon per gallon. Dissolve it in tank water before adding it. Perform daily 100% water changes, making a fresh salt solution each day. Treat for a maximum of 10 days.

Thanks for reaching out about Timothy & Lola. Have you tested the water for pH, ammonia, nitrites and nitrates? Correct any problems. Adding non-iodized salt (aquarium salt) at 1 tablespoon per 10 gallons can reduce osmotic stress but is probably not a treatment for fin rot. If fin/tail erosions progress, antibiotics might be needed, therefore a veterinary visit. Good luck.

Consider a broad spectrum treatment such as General Cure by API or Parasite Clear by Jungle Labs. Follow label directions. Plain aquarium salt (NOT table salt) can be used concurrently to aid in healing and to treat minor infection and fin rot. Dissolve up to one tablespoon per gallon of water into a cup of tank water and gently pour it into the tank. Test water chemistry using a home test kit or submitting a water sample. Most pet or fish stores will do this for free or for a nominal fee. Correct any imbalances using aged or conditioned water that is temperature matched to prevent further stress or shock. Use a conditioner such as StressCoat as well. Confirm adequate filtration to maintain water quality.