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Since 1999
Many parameters change during the changing of the RO membrane and filters in a reverse osmosis drinking water system. First, new filters and membrane creates a different water pressure than was present before the change. This is due to the freer flow from the filters and the new membrane.
Always sanitize the system when changing filters and membrane. See our online guide for sanitizing your RO system. Bacterial growth or Biofilm can come from contact with your hands or other means of contact.
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