The Soy Aquaculture Alliance (SAA) and Prairie AquaTech LLC performed a study on how combined ultrafiltration (UF) and reverse osmosis (RO) technologies in a RAS system can increase soy protein use in aquaculture feeds. During the study, two separate feeding trials were conducted using tank-based RAS and rainbow trout.

"Our hope when working with Prairie AquaTech on this research was to understand how various system changes can impact diet reactions in farm-raised fish," Andy Tauer, SAA Executive Director, said.

Trial one assessed fish at increasing densities using conventional water technologies with a diet of 13% fishmeal and no soybean meal. Trial two utilized UF/RO systems with a diet of very high soybean meal concentration (40%). Results collected showed that when paired with UF/RO systems, soybean inclusion diets increased trialed fish body weight and reduced mortalities. In future trials, diets containing 20% soybean meal are hypothesized to yield more consistent average body weight compared to fishmeal. 

"Prairie AquaTech was happy with these results and we believe there is value to trial varying inclusion rates and see an even greater return on investment," Tauer added.

Read a technical brief on the research here.