How to Cure Fin Rot on a Fantail

Written by alex burgess Google
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How to Cure Fin Rot on a Fantail
Fantail goldfish are susceptible to fin rot when tank water quality is bad. (Jupiterimages/ Images)

Fantail goldfish can develop fin rot when their immune system is under pressure from an injury, poor water conditions, stress from a new environment or antisocial tank mates. Aeromonas and pseudomonas bacteria occur naturally in most fish tanks and cause no problems when dormant, but they can trigger fin rot in a fish with lowered immunity. If your fantail shows symptoms of fin rot, partially change the tank water to rapidly improve water quality, then treat the water with commercial fin-rot medication.

Skill level:

Things you need

  • Bucket
  • Water dechlorinator
  • Commercial fin-rot treatment solution

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  1. 1

    Diagnose your fantail's condition accurately before starting treatment. Fin-rot symptoms include fraying and white-edged splits along the fins. There may also be bloody streaks in the soft tissue at the base of the fantail's fins. Fighting-related injuries and lesions can develop into fin rot if your fish tank water is unhealthy from lack of proper maintenance.

  2. 2

    Remove about half the fish tank's water. Prepare fresh water in a bucket and include a dose of dechlorinator to neutralise chlorine and chloramine deposits from tap water. Many commercial dechlorinators also contain an anti-stress ingredient and a solution to enhance your fish's natural slime-coat layer to help protect against disease.

  3. 3

    Read the manufacturer's guidelines on the fin-rot solution and add the required amount of medication to the new water. Pour the treated water into your fish tank.

  4. 4

    Complete the course of fin-rot medication following the dosage instructions on the bottle. Change 30 to 50 per cent of your tank water approximately twice a week until your fantail shows signs of improvement.

Tips and warnings

  • Dirty water encourages fin rot in vulnerable fish. Changing half of the tank's water every three or four days for a couple of weeks should cure the problem and prevent a recurrence.

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