I need help real bad. Spent about 4 grand on getting keggles, pump etc to go all grain and nothing works.. I have my march pump below everything with the in/out in vertical position with 1/2inch ID noncollapsable tubing connecting everything and I cant get it working.. When I open my valve on HLT and then turn my pump on and valve to MLT I never fill the tubing -- literally I see it lightly streaming down the side of the tubing and the Pressure coming out the top of my MLT is a dribble then stops. I did everything to purge, not cavitate etc and wont work - all valves are functiong etc. What do???