Used Waterloo/small 1800 gallon per hour Reverse Osmosis. Replaced the high high pressure pump at the end of the 2018 season. Has less than 4 hours on it. 7.5hp rebuilt cdl with factory warranty for the 2019 season. New feed pump at the start of the 2017 season. 2 new membranes at the beginning of the 2018 season. I have only been running 2 membranes and can get 11-12% with one pass. Very good machine. This is a steal!