{TAIL ~ The 5 micron filter} 74 is backwashed by {HEAD ~ means} of pump 58 
{ TAIL ~ The 5 micron filter } 74 is backwashed by { HEAD ~ means } of pump 58
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH