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My fish has tail rot, isn't eating, and melafix isn't working. What now?

Updated On September 23rd, 2025

Pet's info: Fish | Unknown - Fish

My fish has tail rot and he is not eating and his tail is falling off I gave him melafix still isn't getting better what do I do

1 Answer

Most Helpful Answer

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

Veterinarian

Published on September 9th, 2018

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.

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