In semi-commercial RAS for Atlantic salmon smolts, increasing alkalinity led to lower concentrations of TAN, but nitrite or CO2 removal was unaffected.
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Increased alkalinity led to a higher total inorganic carbon loss from the system, which may increase costs when running RAS at this alkalinity.
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Atlantic salmon smolt producers using soft water make-up sources, and maintaining a relatively stringent water quality, should aim for 70 mg/L alkalinity.