Most seafood consumed in the U.S. is imported, with only 2% of Atlantic salmon consumed in the U.S. coming from domestic sources. The result is an enormous seafood trade deficit that represents, among other things, a potential strategic risk for the U.S. food supply. American consumers want high quality seafood caught or produced in a manner that does not negatively impact the environment. Land-based recirculating aquaculture system (RAS) production of Atlantic salmon can provide this option. While RAS is a sustainable method for expanding domestic seafood production, innovations are still needed to improve its economics and overall efficiency.

Our recently completed Wisconsin Sea Grant-funded research project pursued solutions and innovations to improve the economic viability and expansion of land-based RAS salmon production in the U.S.


The Freshwater Institute has long been the premier source for development and growth of sustainable fish farming in the North America, leading the way in state-of-the-art RAS technologies research. For several decades, the Freshwater Institute has used its expertise in aquaculture engineering, aquatic veterinary medicine, aquaculture husbandry and production, industry outreach and water chemistry to address critical issues in the domestic seafood supply.

Over the previous three years, the Freshwater Institute carried out research focusing on two important aspects of land-based RAS Atlantic salmon production: early life mortality associated with ubiquitous aquatic organisms of the genus Saprolegnia (i.e., ‘fungus’), and off-flavor in RAS-raised Atlantic salmon fillets originating from beneficial bacteria in tanks and filters.

Research included:

  • Examining low-dose applications of environmentally friendly hydrogen peroxide and peracetic acid to reduce fungus-associated mortality during the vulnerable salmon ‘fry’ life-stage
  • Assessing the impact of water exchange rates, dissolved oxygen, and swimming speed on the efficiency of removing off-flavors prior to harvest


Outcomes of the Freshwater Institute’s research continue to help inform the growing domestic land-based Atlantic salmon RAS industry, assist with sustainable expansion of the industry, and increase consumer confidence in seafood produced in land-based RAS. Techniques developed to improve production learned in this project are now publicly available online at