Foam fractionation efficiency of a vacuum airlift-Application to particulate matter removal in recirculating systems

► The foam fractionation efficiency and the concentration factor of a vacuum airlift were calculated in sea water and in rearing sea water. ► The influence of airflow and water renewal rates on foam fractionation efficiency was measured. ► In rearing conditions, differences in foam fractionation efficiency were observed before and after feeding. ► Particulate organic matter production by fish was calculated and found to be equivalent to estimations obtained using the feed conversion ratio (FCR).