Behind the Scenes at ATC Patagonia: How Innovation is Shaping Responsible Aquaculture
In November 2025, members of the Global Salmon Initiative (GSI) Fish Health and Welfare Task Force visited the Aquaculture Technology Centre (ATC) Patagonia in Chile – one of the world’s most advanced facilities dedicated to salmon research and innovation.
For many people, salmon farming brings to mind sea cages and coastal sites. But what happens in freshwater - long before fish reach the ocean - is just as important. It is in places like ATC Patagonia that researchers and veterinarians test new approaches to improve fish health, welfare, resilience, and environmental performance.
ATC Patagonia is one of the few facilities globally that brings together nutrition, genetics, fish health management, environmental monitoring and water-quality trials under one roof. Seeing this integrated approach up close offers a window into the scale of science and expertise behind modern, responsible aquaculture.
Alejandro Heisinger, Fish Health Manager at AquaChile, shares why being part of a global platform such as GSI is important to him and his work, and why AquaChile are committed to continuous learning and development through the ATC to help advance responsible salmon farming.
What does a salmon hatchery look like?
A salmon hatchery often looks less like a farm and more like a clean, calm research facility. Inside are rearing tanks where young salmon grow in freshwater during their early life stages.
At ATC Patagonia, researchers can observe fish daily and run controlled trials that would be difficult to conduct in open environments. This level of monitoring provides critical insights that support better decision-making, leading to healthier fish and improved outcomes once salmon are transferred to the sea.
What is a Recirculating Aquaculture System (RAS)?
ATC Patagonia uses a Recirculating Aquaculture System (RAS) – a technology increasingly used in salmon hatcheries around the world to support biosecurity, fish welfare, and efficient water use.
RAS works by continuously filtering and treating water so it can be reused, creating a stable environment for fish.
At ATC, seawater is taken in and then treated through a combination of filtration and UV disinfection to help maintain water that is clean, oxygen-rich, and free of pathogens. Only a small amount of water needs to be replaced daily, making it a more resource-efficient and controlled way to raise juvenile salmon.
What makes ATC Patagonia Unique?
Several features make ATC Patagonia stand out for its innovation research:
- Quarantine and acclimatization: Fish are quarantined for 1-2 months to allow them to acclimatize to the water before trials begin
- Open, accessible tanks: Researchers can observe fish behaviour, health and growth and collect samples throughout trials
- Direct seawater intake and purification: Water is sourced from nearby and treated onsite using modern purification systems
- Multiple trial environments: Fish can be moved into separate tanks depending on the research being conducted
These conditions allow ATC to test how changes in feed, water quality, temperature and other factors affect fish health – providing insights that can strengthen performance across the salmon sector.
Feed Trials: why nutrition is central to fish health and welfare
One of the key activities at ATC Patagonia is conducting feed trials. These trials help researchers understand which nutritional compositions best support juvenile salmon as they prepare for the transition from freshwater to seawater.
Feed is much more than “fish food”. The right diet can improve:
- Growth and robustness: A strong start in freshwater supports long-term fish welfare and performance. At ATC Patagonia, Atlantic salmon can achieve growth rates of around 14.5g per day under optimal conditions
- Disease resilience: Feed can play a role in supporting fish immunity and resilience helping provide protection against some of the challenges the fish may face in the natural environment. In Chile, a naturally occurring bacterium Salmonid Rickettsial Septicemia (SRS) is one of the most significant health challenges in the region for salmon farming. ATC’s research helps identify conditions and approaches that support healthier juvenile salmon before transfer to sea
- Gill and skin health: Gill and skin are critical organs – they are the fish’s first line of defence against environmental stressors and pathogens. Here, veterinarians check for indicators of good health in both to help improve welfare outcomes later in the production cycle
- Product quality: good nutrition also supports overall fish condition – including the development of the characteristic pink/orange colour salmon is known for
Broodstock and breeding: improving outcomes across generations
ATC Patagonia’s research supports AquaChile’s broodstock and breeding programme. By analysing results from juvenile trials, teams can identify which parent fish have produced offspring with the strongest health and welfare outcomes.
Because AquaChile operates its own breeding facilities, they can maintain a high level of traceability and biosecurity, knowing exactly where eggs originate and ensuring strong health standards throughout early life stages.
This approach supports continuous improvement - selecting fish for welfare and resilience, not just growth - and helps build a healthier baseline for fish entering the ocean phase.
Understanding the salmon lifecycle – it takes years not weeks
A key takeaway from the visit was the importance of long-term planning and research.
A salmon's lifecycle is around three years from egg to harvest. That means innovation in salmon farming requires years of testing, monitoring, and investment - and improvements made today may take several production cycles to be fully realised.
At ATC Patagonia, juvenile trials also contribute to a deeper understanding of genetics and performance across generations.
Why GSI visited: learning, collaboration and sharing progress
At GSI, we believe the fastest way to accelerate improvements in sustainability is through collaboration, transparency, and knowledge exchange.
GSI’s Fish Health and Welfare Task Force meets regularly to share best practices and emerging insights across key themes such as:
- Fish welfare monitoring and reporting
- Sea lice management
- Gill health and skin health
- Biosecurity and early life-stage care
- The growing influence of climate change on fish health
By visiting hatcheries and research facilities such as ATC Patagonia, our members can see firsthand the innovation and care that goes into raising salmon responsibly - from the earliest freshwater stages through to ocean transfer.
These insights support continuous improvement across the sector and help ensure salmon are raised with strong welfare standards at every stage – supporting both people and the planet.
