PHAROS: Irish Seaweed Trials Cut Salmon Farm Pollution

• September 4, 2026

The PHAROS project aimed at restoring marine biodiversity and ecosystems, has been featured on the Horizon Europe website with team member Julie Maguire of Bantry Marine Research Station representing the project.

The article highlights how the Irish element of this €9.97 million project has demonstrated the potential of seaweed cultivation to address ocean pollution and habitat degradation. PHAROS, which received €9.49 million in funding from Horizon Europe, involves three lighthouse demonstrations in the Atlantic using nature-based solutions and integrated multi-trophic aquaculture (IMTA). The demonstrations are located in Gran Canaria, Iceland and Bantry Bay in Ireland, all under the framework of the EU Mission to Restore our Ocean and Waters by 2030.

The Bantry Bay demonstration, led by Maguire, combines salmon farming with seaweed cultivation to reduce nutrient waste and enhance biodiversity. The approach uses kelp as a natural cleanup agent, absorbing CO2, ammonia and waste from the salmon farm. According to Maguire, the kelp grows at a remarkable rate, increasing from four kilos per meter to 17 kilos in a single month during spring.

Perhaps the most significant finding is that stable isotope analysis confirmed 93% of the nitrogen absorbed by the seaweed came directly from the salmon farm. The Bantry Bay site also proved to be significantly more biodiverse than a control site with no fish farm, with various organisms inhabiting the seaweed ropes and buoys.

Maguire noted the approach is scalable and could be applied beside any fish farm or eutrophic area. The project has also explored uses for the harvested seaweed, including animal feed, with trials showing salmon grew at the same rate when soy protein was replaced with seaweed protein.

The consortium comprises 25 organisations from across Europe, including Irish partners Bantry Marine Research Station, Munster Technological University and the International Consortium of Research Staff Associations.

Read the full article here: PHAROS – Restoring Marine Biodiversity and Ecosystems.