A mild antiseptic, useful as a quarantine solution to treat fin-rot and ulcers. NT Labs Koi Care Acriflavin is best used in conjunction with Ulcer-Swab and Wound Seal in the treatment of ulcers and other open wounds. 
500ml treats 18000 litres (4000 gallons)

NT Labs Koi Care Flukasol Suspension is an easy to use, ready mixed liquid formula Flubendazole. Anti-Fluke treatment ideal for use when treating Skin and Gill Flukes. Use Koi Care Flukasol Suspension when fish show signs of fluke infestation, preferably after confirmation by microscopy.

 500ml Treats 18,200 litres (4,000 Gallons)

Formaldehyde 30% is effective against protozoan parasites and flukes. It is especially useful in treating flukes because of it's ability to penetrate mucus and reach the parasites that would otherwise be protected from other bath treatments.
Caution:  Formaldehyde is a hazardous chemical and should be handled with great care, please read the warnings on the label carefully. 500 ml treats 34000 litres (7500 gallons)

NT Labs Koi Care Malachite is an effective treatment for external parasite and fungus infections. When used together with formaldehyde it's activity is enhanced which means that less malachite can be used. High dose or frequently repeating dosing can damage the gills of the fish. If the required effect has not been achieved after two treatments, take further advice to establish the real cause of the problem.
Please note: The warnings on the label and handle the product with care. 500 ml treats 40,000 litres (8800 gallons)