Ten days on from the introduction of salmon to Aquatraz's innovative cage design, all indicators pointed to a production system more effective than was anticipated.

With 184,500 fish, and salinity levels similar to the sea, oxygen saturation is 10 percent higher than benchmarks and turbidity (the number of particles in the sea) is far lower than the benchmark, between 0.2 and 0.8.

The company has also measured temperatures around 0.5 degrees above the benchmark.

"All these factors are positive for the fish to thrive," said Alf Reidar Sandstad, the entrepreneur behind the Aquatraz design.