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How Reverse Osmosis Water Systems Work

Reverse osmosis is the process in which water molecules are forced through a semi-permeable membrane under pressure. Think back to high school science lab. Remember the experiment with an egg in a glass of water? Once the shell was removed, water traveled through the membrane to balance out the pressure. Culligan RO systems work in a similar way – just reversed.

  1. First, tap water flows through a sediment filter to remove dirt, rust, and other solid objects.
  2. Then the water then flows into a carbon filter which removes 98% of the chlorine and organic chemicals.
  3. The third step is what differentiates an RO system from other filters. Here, pressure greater than the normal osmotic pressure is applied to the water. The reverse osmosis membrane then separates up to 99% of the dissolved contaminants from the water molecules. These removed impurities are rinsed down the drain leaving behind only pure, clean water.
  4. This water is stored in a reservoir tank, typically located underneath the sink.
  5. The final step involves pushing water through a final carbon block "polishing filter" accessed through a special faucet on your sink or refrigerator dispenser before it reaches your glass.

You should first have your water thoroughly tested, if you believe you may need a reverse osmosis water system. You need a test that checks for a broad range of contaminants (not just to see if the water contains pathogens). The county will usually test for pathogens if you ask, but as a homeowner, it is best to get a complete test of the water to detect for mineral content, PH, turbidity (cloudiness), and a host of other contaminants. Culligan Water will do this for you for free!

A Culligan Water reverse osmosis system is the best way to achieve great tasting water today!

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