Climate change and associated surface water temperature rise is major threat for the marine aquaculture industry worldwide. The success of marine aquaculture depends heavily on the favorable conditions of temperature, dissolved oxygen, pH and nutrient levels in water. During summer months, the increase in surface water temperature may cause metabolic distress and asphyxia, resulting in stress and mass mortality of fish. Upwelling using air bubbles is being investigated as a method of controlling water temperature. Upwelling is a process in which the deeper, colder water is lifted to surface providing thermal mixing and circulation of oxygen and nutrient rich water. In winter months, the deeper and relatively warmer water could also be upwelled to the surface to provide more favorable conditions for fish growth and keeping the water surface ice free. Although there is anecdotal evidence that the CanadianPond upwelling systems can provide adequate upwelling, their performances are not quantitatively assessed. Thus, the main objectives of this study are to conduct the validation and verification trials of the CanadianPond upwelling systems (i.e., SalmoAir® and OctoAir-60) for estimating their upwelling performance for use in marine aquaculture operations. This objective was achieved by conducting a field trial with the upwelling systems placed at 20 m below water surface for the system's upwelling rate measurement, supplemented with numerical analysis.

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