Kusuri Formalin & Malachite Green – Premixed Koi Pond Treatment
Kusuri Formalin & Malachite Green is a ready-to-use, full-strength pond treatment formulated for the control of common external parasites in koi and ornamental ponds. The combination of formalin and malachite green is particularly well known for its use against white spot (Ichthyophthirius multifiliis) and other external parasite problems.
The premixed formulation makes treatment straightforward, providing a convenient solution when a pond-wide parasite treatment is required.
Key Benefits
- Ready-to-use premixed formulation
- Contains formalin and malachite green
- Suitable for pond-wide parasite treatment
- Particularly useful when treating white spot
- Easy to dose directly into the pond
- Suitable for koi and ornamental ponds when used according to the manufacturer’s instructions
Dosage & Treatment
Dosage: 100ml per 1,000 gallons (approximately 4,546 litres) of pond water.
Treatment can be repeated up to a maximum of three times, with 7 days between treatments, where required.
Do not use at water temperatures below 10°C (50°F).
Important Safety Information
Do not use Kusuri Formalin & Malachite Green in ponds containing salt. Ensure any salt treatment has been removed or diluted appropriately before using this product.
Always read, understand and follow the safety and application instructions supplied with the product before use.
When handling pond chemicals:
- Wear suitable disposable vinyl or latex gloves.
- Wear appropriate eye protection.
- Do not eat, drink or smoke while handling the product.
- Keep the product away from children and pets.
- Use only as directed by the manufacturer.


