A　laboratory-scale　anaerobic/anoxic/oxic　reactor　system　was　used　to　treat　synthetic　brewery　wastewater　for　I　year.　The　objectives　were　to　enhance　denitrifying　phosphorus　removal,　improve　biological　nutrient　removal　and　reduce　operating　costs.　Three　operational　strategies　were　tested:　(1)　controlling　nitrate　recirculation　to　stimulate　the　growth　of　denitrifying　phosphate-accumulating　organisms;　(2)　adjusting　the　volume　ratio　of　the　anaerobiclanoxic/oxic　zones　to　enhance　anoxic　P　uptake;　(3)　bypassing　a　part　of　the　influent　flow　into　the　anoxic　zone　to　maximise　anoxic　P　uptake　and　denitrification.　The　results　showed　that　not　only　was　anoxic　P　uptake　enhanced　but　also　energy　consumption　for　aeration　could　be　reduced　when　the　anoxic　effluent　NO3--N　concentration　was　controlled　between　1　and　3　mg　L-1.　The　optimal　volume　ratio　of　the　anaerobic/anoxic/aerobic　zones　in　this　system　was　found　to　be　1:1:2.　The　optimal　bypass　flow　ratio　was　0.32.　The　results　indicated　that　the　optimal　strategies　could　improve　treatment　performance　and　reduce　operational　costs,　but　there　was　still　a　challenge　to　treat　wastewater　with　low　ON　ratio.　(c)　2006　Society　of　Chemical　Industry.