{TAIL ~ A fixing carrier} for fixing {HEAD ~ an activated sludge} employed in a sewage or waste water treatment in which: 
{ TAIL ~ A fixing carrier } for fixing { HEAD ~ an activated sludge } employed in a sewage or waste water treatment in which :
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH