Fluid flow through the return side filter may be accomplished using {HEAD ~ any} of three described alternative embodiments, including upflow, {TAIL ~ downflow}, and direct feed 
Fluid flow through the return side filter may be accomplished using { HEAD ~ any } of three described alternative embodiments , including upflow , { TAIL ~ downflow } , and direct feed
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH