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My Discus fish has fin rot and black spots. How do I treat it?

Updated On September 23rd, 2025

Pet's info: Fish | Cichlid

How to treat Discus Fish 's Fin Rot disease ? My Discus fish has black coloration with fast breathing and he has fin rot ? So how to treat them please reply soon

1 Answer

Most Helpful Answer

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Answered By Dr. Massimo Orioles, DVM, Cert AVP, MRCVS

Veterinarian

Published on September 5th, 2019

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.

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