I am the hatchery manager for Gårdsfisk, a land-based fish-farming company in southern Sweden. Conventional fish farming in the sea can have big environmental and welfare impacts. Fish can escape from their enclosures, they can spread disease, and waste from the farms can over-fertilize waterways and ruin aquatic ecosystems. Our aim is to produce the most sustainable fish in the world.

We farm red and silver tilapia and clarias, a type of catfish, and grow our fish indoors on a farm using a recirculating aquaculture system. The total water volume in our system is 2,000 cubic metres, less than in an Olympic swimming pool. We use the fish faeces in the waste water from our tanks to fertilize surrounding farmland, and we reuse the tank water on our own gardens to reduce our environmental footprint. We use renewable energy wherever possible: our fish-farming buildings are covered with 600 square metres of solar panels. In summer, when we have up to 18 hours of sunlight a day, the panels can produce all the electricity we need.

My job is to select the best breeding stock. In this photo, I’m studying the broodstock, which are separated by sex into holding tanks so that they do not breed. The white containers are for feeding but they aren’t connected; we hand-feed our brood stock so that we can check on their welfare several times daily. The black barrels are for collecting fish faeces. My gumboots are part of our biosecurity measures; parasites can become a problem.

Before we introduce breeder fish to our spawning tanks, we observe each one to choose the best, going by their rate of growth, their general appearance and the quality of their oocytes or sperm.

What I love about my work is that I can do so many different things in a day. I can be harvesting or grading fish in the morning, and speaking to South American customers in the afternoon. In August, we received a visit from the king and queen of Sweden.