NT Labs Formalin 7-2.5ltr- Anti-parasite treatment for Koi. NT Labs Koi Care Formalin 7 treats persistent parasite infections of pond fish such as White Spot, Trichodina, Costia and Chilodonella. Recommended dosage: A course of treatment over 7 applications. Use when fish are flashing against rocks, gasping at the surface etc. 10ml treats 700 litres 2.5 litres treats 7 x 25,000 litres Add one dose every week for 7 weeks. Switch off UV until 5 days after the final dose has been added. Have you tried other treatments for persistent fish ailments, M Green 7 and Acriflavin 7?
