The treatment, Ectosan, which has been developed by the UK-based company, was delivered through the company’s CleanTreat filtering system - which removes any detectable traces of medicine from treatment water before it is discharged into the sea - meaning that the treatments had no environmental impact.
Benchmark believes that Ectosan can eventually achieve worldwide sales of £40-50 million annually. It will continue field trials in key markets through 2018 and 2019.
Chief executive Malcolm Pye said: "This is major breakthrough for Benchmark and the salmon industry. The combination of our next generation sea lice treatment, together with CleanTreat represents a transformational change in the battle against one of the industry's greatest challenges, and a big step towards a future where no medicinal residues are discharged directly into the oceans.
"Given its significance to the industry and interest expressed by our customers, we expect to see substantial demand for the treatment and look forward to providing the treatment more widely upon regulatory approval."
Benchmark would not comment further on Ectosan or how it works.
The company launched CleanTreat at Aqua Nor in Trondheim in August. A Benchmark spokesperson said: "CleanTreat can also be used with other bath treatments. Essentially CleanTreat could transform the salmon industry in terms of reducing environmental impact. There isn't another system like it, it's the first of its kind."
See a video outlining the CleanTreat system below.