Pressure gauges at input and output of wound and carbon filters give an indication of pressure drop across this filter pair and thus the amount of material built up on filters. High pressure gauge shows pump outlet (RO cartridge inlet) pressure which can be adjusted by turning needle vale below gauge. Flow meters show permeate (a bit above 1 LPM) and concentrate (a bit below 2 LPM) flows indicating recovery of around 40%. Unit is fed with softened water so high recovery is not a factor in membrane fouling from CaCO3 deposition.