by Priyal Shah, Assistant Editorial Manager, International Aquafeed & Fish Farming Technology, India.
Sea Eight specialises in the sustainable farming of Solea sole fish on land. They represent a significant step in sustainable aquaculture, showcasing how innovation and environmental responsibility can transform seafood production. As one of only three companies worldwide farming sole on land, Sea Eight is among the largest producers and is currently expanding with a new on-growing facility in Spain, which will increase total production to approximately 1500 tonnes.
As a land-based farm using advanced recirculating aquaculture systems (RAS), Sea Eight makes it possible to cultivate Solea sole locally, providing a healthy and high-quality protein source while protecting marine ecosystems. This approach allows Sea Eight to combine sustainability with efficient production, aligning with its mission to deliver access to Solea sole for future generations while respecting animal welfare.
The Portuguese facilities, located in Póvoa de Varzim and Aveiro, are part of an integrated network including the main hub in Cambados, Spain. Each site features state-of-the-art infrastructure designed by Sea Eight’s research and development team, with fully certified systems that cover all stages of production—from hatchery to grow-out and processing. This closed-loop design ensures optimal biosecurity, consistent product quality and the highest standards of fish welfare.
Sea Eight’s Farms Across Portugal and Spain
Sea Eight acquired two farms and transformed their production from Turbot to Solea senegalensis by implementing advanced RAS technology to enable fully land-based farming. Sea Eight operates four farms across Spain and Portugal, with two locations in northern Spain and two in Portugal. The Portuguese hatchery supplies five million juveniles annually to three on-growing facilities, which together produce around 1000 tonnes of Solea.
At present, fish are transported between the two sites by trucks. However, the company plans to integrate the hatchery and grow-out operations into a single premises, connected by a direct piping system. This will allow the fish to be pumped from one stage to the next, enabling streamlined operations and centralised control over the entire production process.
Optimising Solea Farming with R&D
Sea Eight has developed expertise across every stage of Solea production, from genetic selection and in vitro fertilisation to feeding strategies using an in-house formulated diet tailored specifically for their systems. All of their production systems are designed and developed in-house, with a strong focus on automation to reduce labour costs.
The company is also exploring the integration of artificial intelligence to manage the complexity of the process, which requires careful coordination of genetics, feeding regimes and water quality. By combining advanced technology with deep biological knowledge, Sea Eight aims to optimise production while maintaining the highest standards of efficiency and fish welfare.
In-House Feed Production
This R&D enables them to produce Solea year-round, ensuring a consistent supply even during peak consumption periods, such as the summer months, and distributing across Europe. At their facilities, they cultivate their own microalgae to feed the hatchery, rather than relying on external suppliers like Seafeed or Plantonic. This in-house production allows them to maintain full control over feed quality and consistency, supporting optimal fish growth and overall product reliability.
Water Efficiency Through Advanced RAS Technology
At Sea Eight, water efficiency is a cornerstone of their operations. Using their own Recirculating Aquaculture System (RAS) technology, they require only 3% of the water that conventional systems would use. Developed and optimised in-house after years of refinement—and building on expertise from the Spanish facility in Galicia—Sea Eight’s RAS ensures that input and output water is fully treated before returning to the environment, free of organic matter. The system also maintains stable, marine-like conditions for Solea, combining sustainability, process control and food safety in a state-of-the-art land-based aquaculture solution.
Sea Eight’s Commitment to Sustainable Aquaculture
Sea Eight is committed to environmentally responsible aquaculture, ensuring that their operations have minimal impact on the ocean. All water entering and leaving their systems is fully treated and heat recovery is applied to reduce the temperature difference between farmed water and natural seawater. Solar panels on the facility roofs further decrease energy consumption.
Sea Eight also integrates a circular economy approach by cultivating algae at the system’s outlets, capturing residual nutrients and optimising water quality. Through these measures, the company minimises environmental impact while producing high-quality Solea in a truly sustainable way.
Future Outlook
Looking ahead, Sea Eight is planning a major expansion in northern Spain with a EU€55 million investment to establish an integrated facility capable of producing an additional 1500 tonnes of Solea, covering the full cycle from eggs to final product. The goal is to build a large-scale operation that maximises economies of scale with ambitions to reach 3000 tonnes by 2028–2030. This project will create over 100 jobs.
Beyond this, Sea Eight is pursuing licenses and land for further expansion and exploring opportunities to acquire other companies, including those needing financial or operational support. With this approach, the company aims to strengthen its high-end product portfolio while positioning itself for sustainable growth and market leadership.
