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Kusuri Formalin 30%


Kusuri Formalin 30%

Kusuri Formalin 30% is an effective koi parasite treatment which can be used against Skin Flukes, Costia, White Spot and other parasites. 

Formalin 30% is a very active chemical and is best used with Malachite for the effective koi treatment of most single cell parasites including White Spot, Costia and some Fluke infestations.

For best results  we recommend using this product with Kusuri Malachite Green 2% Solution.


The normal course is 3 treatments 5-7 days apart.

  • 250ml treats 3,325 gallons
  • 500ml treats 6,650 gallons
  • 1 Litre treats 13,300 gallons

This koi treatment is for use only with koi carp and should only be used in pond temperatures above 10°C (50°F). We do not recommend the use of Formalin with any salt in solution.