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Water Doctors SMP-3000 5 Stage RO Reverse Osmosis System Replacement Water Filters and RO Reverse Osmosis Membranes. Huge replacement water filter inventory. Millions sold.
Water Doctors Pro-4000 4 Stage RO Reverse Osmosis System Replacement Water Filters and RO Reverse Osmosis Membranes. Huge replacement water filter inventory. Millions sold.
Water Doctors PRO-2000 Under Sink Water Filter System With Quick Change Replacement Water Filters. Huge replacement water filter inventory. Millions sold.
Simply enter your Feed Water TDS and RO Water TDS into the boxes above and click "Submit". The percentage of TDS Rejection will be displayed. We normally recommend membrane replacement once you drop below 75%. This may vary in areas with high TDS in the feed water.
See our selection of TDS meters under Water Tests