Large selection of replacement water filters, reverse osmosis membranes, testing kits and water filter system repair parts. From one water filter or membrane to case quantity discounts.

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The 3 stage, 4 stage and 5 stage reverse osmosis systems install exactly the same. The only difference is the addition of a carbon water filter before the membrane on the 4 stage RO system and two of them on the 5 stage system. The first carbon filter is normally a GAC water filter (hard outer shell). The second carbon water filter is normally a carbon block (netted outer shell).