Phosphorus (P) is a fundamental fertilizer in food production, but it also represents a major environmental problem as it is a main driver of water eutrophication. Therefore, it requires removal from wastewater prior to disposal. The enhanced biological phosphorus removal (EBPR) process based on the capability of certain bacteria to store large amounts of intracellular phosphate (polyphosphate accumulating organisms, PAO), has been widely applied in different countries to remove and recover P from wastewater. However, this technology has not yet been implemented in Uruguay. The aim of this study was to evaluate changes in the microbial community within lab-scale reactors for biological P removal, operated under different conditions: different activated sludge (AS) sources from Uruguayan industrial wastewater treatment plants (WWTP) as inoculum, different feeding strategies (synthetic or industrial effluent), bioaugmentation with Tetrasphaera and different durations of anaerobic/aerobic stages.