Potassium Permanganate

Used for the treatment against parasites, Trichodina & Costia as well as a general disinfectant for ponds and equipment.

SKU: Potassium Permanganate 250g Category:

Kusuri Potassium Permanganate is another popular powdered chemical for various applications.A good disinfectant for ponds and nets. Excellent for the eradication of Trichodina & Costia, and other parasites.

It will discolour water for up to 7 days, and can be used down to 10°C (50°F).

At higher temperatures Potassium Permanganate removes oxygen from pond water, it is advisable to keep an air stone running and add more air if possible.

Kusuri Hydrogen Peroxide 6% can be used to increase the oxygen levels in pond water and also remove the discolouration from the pond water after a course of Kusuri Potassium Permanganate has oxidised from pink to brown.

NEW altrunative treatment for Coastia and Trichodina, Kusuri Acriflavine & Malachite Green Premix

From 14th of January 2013 it is illegal to send Potassium Permanganate via the Post Office as it is classified as an oxidising agent. This will incur our small order carriage charge of £6.99 if the order is under £35 because of the specialist courier we use.

Kusuri recommend NOT using Potassium Permanganate with salt.

Please ensure that you read, understand and follow, all Health and Safety guidelines on the packet.

Please do not eat, drink or smoke whilst handling chemicals.

Wear disposable vinyl or latex gloves and appropriate eye protection.

Dosage Instructions

Dosage: 6.8g per 1000 gallons (4546 Litres) of pond water. DO NOT OVERDOSE. Over dosing can cause fish fatalities

Do not use below 10°C (50°F).

How To Use

Switch off UV steriliser until course of treatment is complete. Ensure pouch remains sealed after each use. Measure the correct dose and place in a bucket of hot water. Aerate for 20 minutes then disperse solution evenly around the pond over a one hour period. Do not use below 10°C. Potassium Permanganate will turn the water purple. Re-dose as required to achieve a minimum total of 15 hours of purple coloured water. When pond water is above 18°C, add more oxygen to the pond as Potassium Permanganate strips oxygen from the water. If you have gill flukes, treat with Fluke-M or Fluke-P first to prevent fish losses, followed by a treatment of Potassium Permanganate for Trichodina or Coastia. At the end of a course of treatment use Kusuri Hydrogen Peroxide to reoxygenate and help clear the water. In warmer water, if you see the fish struggling during a dose of Potassium Permanganate, Kusuri recommend using Kusuri Hydrogen Peroxide to reoxygenate and assist in neutralising the Potassium Permanganate.

Frequently Asked Questions


  • Q. Why does Kusuri recommend re-dosing numerous times to achieve 12-15 hours of purple/pink water?
  • A. Kusuri recommend re-dosing once the purple/pink colour of your pond water has turned brown. If your first dose goes brown after 2 hours, then re-dose and time the period that your water takes to go brown again. This could possibly be 6 hours. 2 hours plus 6 hours equals 8 hours total time. A further dose would be required to achieve the recommended 12-15 hours of purple/pink. Kusuri recommend 12-15 hours of purple/pink water to eradicate the full life cycle of Costia or Trichodina. Due to resistance using Potassium Permanganate we have had many occasion where a client has always treated for approximately 4 hours, then assuming they have eradicated all of the parasites. Unfortunately the parasites that have not been killed during this 4 hour period then build up resistance to that dosage regime.
    Dosing 12-15 hours ensures a very high eradication level, preventing future resistance.
  • Q. When do you recommend using Kusuri Hydrogen Peroxide and why?
  • A. Kusuri Recommend using Hydrogen Peroxide on these three occasions.

1. To neutralise Potassium Permanganate at the end of a course of treatment. It will also re-oxygenating your pond water and assist in removing the brown colouration of the oxidised Potassium Permanganate.

2. Kusuri Hydrogen Peroxide can be used half way through, or at any point during a treatment, if the fish are struggling due to oxygen depletion.

3. A dilution of 50/50 of Kusuri Hydrogen Peroxide with water, can be used to cauterise the leading edge of fins after trimming. This solution can also be very useful when cleaning a large ulcer if there is any bleeding, to aid cauterising and sealing the wound. Care must be taken not to get this mixture healthy tissue, as it will burn.

  • Q. I have Costia, Trichodhina and Flukes, which should I treat for first?
  • A. After accurately identifying the above parasites, it is important to treat for Fluke first.
    Kusuri Potassium Permanganate will reduce the oxygen level in your pond. If your Koi have Gill Flukes they will very often be struggling to absorb enough oxygen. This is due to the increased mucus build up in the gills, caused by the parasites irritating the gill lamellae. At this stage if you were to treat with Kusuri Potassium Permanganate, the oxygen level would be depleted sufficiently to cause fish losses, due to oxygen starvation. Always treat for Flukes first! Then Costia and Trichodina.
  • Q. What time of day should I start my treatment?
  • A. It is always advised to start your treatment as early as possible so that your Koi and water colour can be monitored for the 12-15 hour treatment duration. Never leave your Koi unattended during a treatment and if necessary net the pond to prevent fish jumping out.
  • Q. Do I have to use the same dose rate of 6.8g per 4546 litres (1,000 gallons) for each additional dose?
  • A. Kusuri recommend using the dose rate of 6.8g for each additional dose, once the water has gone brown. Do NOT overdose.
  • Q. Do I need to add more aeration to my pond prior to treating with Kusuri Potassium Permanganate?

  • A. Yes, please remember the warmer the water the less dissolved oxygen it will hold. Extra aeration is critical above 16°C.
  • Q. Why does my pond water turn brown after 30-60 minutes?
  • A. Ponds which contain a high organic loading e.g. dirty filters, organic matter on the pond floor or high levels of blanketweed, will reduce the length of time Potassium Permanganate remains active. When Potassium Permanganate is first added to the pond, the water will take on a deep purple colour. Once the water goes brown the treatment is inert and no longer active. Please ensure your pond and filters and cleaned prior to using Kusuri Potassium Permanganate as it will be more effective.
  • Q. My pond has green water, can I use Kusuri Potassium Permanganate?
  • A. If the pond has any particulate organic material (green water), then much of the oxidation reaction will take place with the green water rather than the parasites or bacteria you are targeting. For this reason, a Kusuri Potassium Permanganate treatment will not be effective in green water. Ensure your UV filter bulb has been replaced after 12 months, as they loose effectiveness beyond 12 months. With a new UV bulb the water will clear within a matter of weeks. 

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Health And Safety

Store in original container between 2°C and 30°C. Keep out of reach of children. For animal pond water treatment only. Always wear protective gloves and goggles when handling chemicals. Use within 12 months of opening. Do not use in conjunction with any other medication. Do not use with salt.