Lice-Solve (previously known as Mectinsol) is a new and exciting development of a tried and tested treatment for external parasites in ornamental fish.

Lice-Solve is a specially developed unique formulation containing emamectin for the treatment of external parasites such as Argulus (fish lice) and Ergasilus (gill maggot) in ornamental fish including koi. Clear these parasites from your koi with one single immersion treatment in the pond or tank.

Emamectin was originally developed for the control of sea lice in farmed salmonids by oral administration. Lice-Solve has been specifically developed by Fish Treatment Ltd for the hobbyist, and its easy-to-use formulation means that fish can be treated by immersion in the product – avoiding the need for the problems associated with oral administration of medicines to ornamental fish. It can be used directly into the pond or tank where the fish are kept, or fish can be moved into a separate treatment tank for the treatment period. Make sure that the water is well oxygenated during treatment.

Sufficient product should be used to ensure that you use 4 grams of Lice-Solve per 1000 litres of pond or tank water. There are two convenient sachet sizes -

10g - which is sufficient for 2500 litres (550 gallons)

100g - which is sufficient for 25000 litres (5500 gallons)


Turn off the UV and bypass any carbon filters. Put the required number of Lice-Solve sachets into 10 litres of pond or tank water in a clean bucket and mix well. Pour this suspension into the pond or tank and rinse the bucket out with pond or tank water to make sure you have used all of the product. Leave for 12 hours and then turn on the UV and activate the carbon filter.

Repeat treatment after one month to ensure developed eggs are killed. Use once a year as a routine treatment to prevent the build-up of parasites such as Argulus and Ergasilus, and to take care of the parasites or their eggs overwintering.

Caution – while treating fish with any medicinal product please ensure they are well oxygenated, and perform regular checks.

Lice-Solve is manufactured to the highest European Pharmaceutical standard under a Good Manufacturing Practice (GMP) Licence. It is sold under thre Small Animal Exemption Scheme.

Lice-Solve has been specially developed for use by a fish vet. You can be assured of its quality.

Extensive trials have shown no toxic effect of emamectin on the natural wildlife of the pond, and the active ingredient rapidly biodegrades in water in sunlight. Emamectin is deactivated by UV light and carbon filters so these must be turned off during use of the product.

Do not use in animals other than those indicated. Serious reactions, including deaths, have been reported in dogs (especially collies, Old English Sheep Dogs and related breeds), tortoises and turtles treated with products containing the active substance.

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