Northwest Fisheries Science Center

Systems Engineering

For aquatic culture systems, system engineering focuses primarily on materials selection, water quality maintenance, feeding/harvest systems, and discharge control and treatment. Key unit processes for water quality include: aeration, degassing, carbon dioxide stripping, ammonia control, and solids removal. The importance of each process depends on species, size, density, and type of production system. Water quality maintenance is especially difficult for larval marine fish because of their small size, feeding requirements, and sensitivity to physical and chemical parameters. Current research in the system engineering group is focused on (a) development of aeration and degassing systems, (b) improved solids removal systems for circular tanks, and (c) reduction of energy use in production systems.

Recent Publications

Colt, J., Summerfelt, S., Pfeiffer, T., Fivelstad, S., Rust, M. 2008. Energy and resource consumption of land-based Atlantic Salmon smolt hatcheries in the Pacific Northwest (USA). Aquaculture, 280, 94-108.

Colt, J., Kroeger, Rust, M. 2010. Characteristics of oxygen flow through fine bubble diffusers used in the aquaculture hauling applications. Aquacultural Engineering 43, 62-70.

Colt, J., Watten, B., Pfeiffer, T. 2012. Carbon dioxide stripping in aquaculture – Part III: Model Verification. Aquacultural Engineering, 47, 47-59.


John Colt, EFS Division, NWFSC
Eric Kroeger, EFS Division, NWFSC


Jim Liou, Civil Engineering, University of Idaho, Moscow, Idaho
David Smith, Waterways Experiment Station, Vicksburg, Mississippi
Asbjorn Bergheim, International Research Institute of Stavanger, Norway