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NT Labs

NT Labs Formalin


NT LabsAnti-Parasite Treatment for Koi

Treats: White Spot, Trichodina, Costia, Chilodonella.

When to use:

  • Formaldehyde 30% is effective against protozoan parasites.  It is especially useful in treating parasites because of its ability to penetrate mucus and reach the parasites that would otherwise be protected from other bath treatments.
  • Formaldehyde can also be used in combination with Malachite to treat protozoan parasites.


  • Switch off UV for at least 5 days.
  • Wait 10 days after the final dose before treating with a different medication.
  • If you feel that a repeat dose is necessary, check your diagnosis carefully, a different medication may be more suitable.
  • Can be used with Malachite to treat parasites.


  • Use when water temperatures are below 10°C or above 30°C.

10ml per 250 litres/55 gallons

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