The maximum recommended flow rates depend on the contamination of the fluid being filtered and the viscosity of the fluid. For "clean water" such as municipal water feed to an RO system the maximum flow rate is 5 gpm (18.9 lpm) per ten-inch length (TIE) of filter; e.g. a 40" filter will have 4 TIEs.
As the contamination level increases, flow rates should be reduced to increase service life and more effectively utilize the depth filters’ media. For moderately contaminated fluids (10 ppm of solids) a flow rate of 2.0 gpm (7.6 lpm) /TIE is suggested.
As fluid viscosity increases above 1 cps (i.e. the viscosity of water) the pressure drop will rise proportionately. Use the flow vs. pressure drop charts on the product fact sheet and multiply the value by the fluid viscosity to obtain the pressure drop. Size the filtration system to fall below the allowable maximum pressure drop.