New case study: CleanTreat®: water treatment technology for sea lice management

A water treatment technology for pest management in aquaculture

Managing sea lice is a challenge in salmon farming, requiring Integrated Pest Management (IPM) strategies that combine multiple tools, including medicines. However, strict environmental discharge limits can restrict the use of certain treatments, reducing farmers’ ability to manage lice effectively and increasing the risk of resistance.

CleanTreat® is a purification system developed in Scotland and currently operating in Norway. It removes medicines from treatment water before returning it to the sea, offering a way to meet discharge regulations while enabling effective treatments. In 2022, a pilot study tested CleanTreat® at a Scottish salmon farm using Salmosan® Vet (active ingredient azamethiphos) to assess its performance in reducing environmental impact. Valued at over £630k, the project partners were Benchmark Animal Health Ltd., Mowi Scotland Ltd., and the University of Stirling.

The trial involved dosing seawater with Salmosan® Vet (without fish) and passing it through the CleanTreat® system. Analysis showed an average removal efficiency of over 90% of azamethiphos. Environmental modelling compared traditional tarpaulin treatments, wellboat treatments, and wellboat treatments with CleanTreat®, demonstrating significant potential for reducing environmental risk and improving treatment flexibility.

This was the first use of CleanTreat® in Scotland and globally with Salmosan® Vet, marking a major step toward sustainable sea lice management. By enabling higher treatment efficiency within regulatory limits, CleanTreat® could allow farms to treat more quickly, improve fish health and welfare, and reduce resistance development. Commercial adoption would support Scotland’s aquaculture growth while meeting environmental standards.

Future work will include trials with live treatments, market assessments, and integration with wellboat operations. If scaled, CleanTreat® could transform IPM strategies, offering farmers a practical, environmentally responsible solution for managing sea lice.

The full title of this project is ‘Use of CleanTreat® water treatment technology to support integrated pest management’.

Read the case study