Similarly, {TAIL ~ the purified water} is returned to the pool of {HEAD ~ water} after ozone elimination, temperature adjustment and chlorination 
Similarly , { TAIL ~ the purified water } is returned to the pool of { HEAD ~ water } after ozone elimination , temperature adjustment and chlorination
OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH