looking for some input on what I'm doing wrong . we have a small commercial ro system that came out of a restaurant for there water . it's a 25x40 vessel with a procon pump. We have two pre filters before the unit. Our sap is coming in at 1.3 and our first pass can get up to 2% and on a second pass we are lucky to get a half a percent and even after our 4 pass we might get 3 to a 3.5%.looking for ideas