The Freshwater Institute is the only U.S. participant in the CtrlAQUA research center, which the Norwegian Research Council and the world’s largest salmon farming companies (such as Marine Harvest, Grieg Seafood, Cermaq, Leroy Seafood, to name a few) have funded at nearly $25 million over the next eight years. The center seeks to find ways to make closed-containment aquaculture systems a reliable and economically viable technology for producing larger Atlantic salmon, primarily post-smolt at sizes up to 1000 grams (2.2 pounds). 

Our Role

The Freshwater Institute is part of CtrlAQUA’s Departments of Technology & Environment and Preventative Fish Health, providing extensive advisory and technology support to partners in Norway. Scientists and engineers at the Freshwater Institute are leading two projects in collaboration with Norwegian teams.

The HYDRO project, which began in 2015, looks at hydrodynamic challenges in huge culture tanks (more than 1,000 cubic meters) and seeks to develop models to determine how variables—such as splitting of water flow to the upper and lower dual-drains, inlet nozzle velocities, and the tank hydraulic retention time—impact solids flushing, water rotational velocities, and water mixing through the tank. Water rotational velocity within circular tanks can be used to optimize swimming speed for Atlantic salmon growth and disease resistance. Uniform water mixing is required so that fish are exposed to the same water quality throughout the tank. There is great potential to reduce fixed and variable costs with the application of large circular-type culture tanks of capacity near 1000 m³ for smolt and post-smolt production.

The PHOTO project is examining how different photoperiod regimes—or how long they are exposed to light—affect Atlantic salmon quality and robustness as post-smolts are raised in a freshwater reuse system. Producing larger smolts in freshwater systems represents a new variation in land-based post-smolt production. Photoperiod has been shown to have a strong influence on both smoltification and the initiation of sexual maturation. However, determining the optimum photoperiod regime during pre-growout freshwater rearing has not been adequately assessed. The PHOTO project is being conducted at the Freshwater Institute’s research system in 2016 and 2017.

Why This Project Matters

Improving technologies to produce larger salmon in closed-containment systems makes it possible to sustainably raise quality salmon for consumers with less environmental impact. It also shortens or potentially eliminates the time that these fish are raised in ocean pens, where they are at greater risk from sea lice, fish pathogens, algae blooms, super chill, and storms, as well as escape.

Learn More

CtrlAQUA Annual Report 2017