Kusuri 30% Formalin and Malachite Premix is a ready to use full strength formulation, popular as a pond-wide anti-parasite treatment. It is particularly good for White Spot, Skin Flukes, Chilodonella, Oodinium and most Protozoan Parasites. Do not use below 12.5°C (54.5°F). Please ensure that you read, understand and follow all Health and Safety guidelines on the bottle. Please do not eat, drink or smoke whilst handling chemicals. Wear disposable vinyl or latex gloves and appropriate eye protection. 250ml treats 11,365 litres (2,500 gallons) of pond water 500ml treats 22,730 litres (5,000 gallons) of pond water 1 litre treats 45,460 litres (10,000 gallons) of pond water


Size: *
  • 250ml
  • 500ml
  • 1ltr

Learn More

Use 10ml per 100 gallons (454 litres) of pond water. Treat up to 3 times, 7 days apart. 

DO NOT OVERDOSE. Over dosing can cause fish fatalities.

For use above 12.5°C (54.5°F)

Switch off UV steriliser until course of treatment is complete. Tighten cap and mix well. Use cup supplied to measure the correct dose. Add water to a clean watering can, then add Formalin/Malachite Premix. Gradually sprinkle across the surface area of the pond over a 1 hour period. Do not use below 12.5°C.

Do not use Malachite and Formalin Premix in conjunction with salt.

Stop feeding during the course of treatment because Malachite and Formalin will reduce the bacteria in the filter, continuing to feed will cause an ammonia spike.

Once the course of treatment is complete monitor your water parameters regularly and add good bacteria to restart your filters, such as Kusuri Filter Starter Boost or Kusuri Starter Pink.