PENTAIR GRO 75 Reverse Osmosis Replacement Filter Set Yearly
Reverse Osmosis Filter Set contains 2 carbon block filters and 1 sediment filter.
Filters should be changed yearly on city treated water under normal use and when connected to a SOFT water supply.
Filters should be changed every 6 months on private wells or when reverse osmosis is connected to a HARD water supply.
The sediment filter is the first one on the line and the carbon filters should be installed in the middle and in the final housing.
If your RO has 3 filters on the bottom and a membrane (any type) across the top.