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    Everything You Need to Know About Reverse Osmosis

    glass of water
    glass of water

    Everything You Need to Know About Reverse Osmosis


    What Is Reverse Osmosis?

    Reverse osmosis is a process that removes foreign contaminants, solid substances, large molecules and minerals from water by using pressure to push it through specialized membranes. The system improves water for drinking, cooking and other important uses.

    How Does Reverse Osmosis (RO) Work?

    As its name implies, RO takes osmosis, a natural process that occurs in every cell-based organism—plants, animals and even people—and reverses it.

    To understand reverse osmosis, you first need to know – what is osmosis? During regular osmosis, a diluted solution passes through a semipermeable membrane and flows into a more concentrated one. Example: When your fingers become “prune-y” after swimming in the ocean. Through osmosis, the water in our bodies passes through our skin, out to the water around us.

    Now, here’s how reverse osmosis works:

    • Unlike osmosis, which is a passive process, reverse osmosis requires external force (pressure) to work.
    • Pressure is applied to a highly concentrated solute solution, such as salt water, to pass through a membrane to a lower concentrate solution.
    • The membrane allows water to flow through but blocks out larger molecules, like contaminants.
    • The reverse osmosis process leaves higher concentrations of solute on one side and only the solvent, or freshwater, on the other.

    How Does A Reverse Osmosis (RO) System Work:

    Reverse osmosis is a method that can be applied to water filtration to help remove other minerals, substances, molecules and impurities from the water that runs throughout your house. RO systems vary depending on the brand and design, but in general, they perform the following functions: pre-filtration, reverse osmosis, drainage and storage.

    Here are the steps of water filtration through a reverse osmosis drinking water system:

    Step 1: Pre-Filtration

    The system connects to drinking water lines and uses a high-pressure pump to propel feed water through. Feed water passes through a series of filters, usually carbon-based, designed to “catch” sediment and mineral deposits before flowing into the reverse osmosis chamber.

    Step 2: Reverse Osmosis

    Here, the feed water is pushed through the semipermeable membrane.

    Think of the membrane as a tightly woven piece of fabric—one that looks virtually impermeable to the naked eye. To give you an idea of how stringent the membrane is, the diameter of a strand of human hair is roughly 100 microns wide. But, in Culligan Water RO Systems, the spaces in the membrane are approximately one micron wide.

    Step 3 + 4: Drainage & Storage

    The reverse osmosis system drains out all contaminants not caught in filters at each stage, and treated water is stored in a small tank until used.

    What Are Common Contaminants Removed By Reverse Osmosis (RO)?

    common contaminants removed by a reverse osmosis water filter

    A high-performing RO system can remove a number of common contaminants found in feed water. These contaminants can include:

    • Salts
    • Particles
    • Colloids: Oil and fat-based molecules
    • Organic bacteria
    • Pyrogens: Protein-based substances produced by bacteria that cause fevers when introduced into the human body


    Is Reverse Osmosis Water Safe To Drink?

     Reverse osmosis water is the healthier, safer choice for you, and your family’s health. Reverse osmosis systems help reduce particles, bacteria and dissolved minerals commonly found in tap water. Moreover, it helps to remove some harder-to-detect contaminants that can be harmful to your health, such as lead and arsenic. Drinking reverse osmosis water can help minimize health risks associated with drinking water with potentially harmful contaminants, such as:

    • High blood pressure
    • Low fertility
    • Skin issues
    • Increased carcinogen creation

    When you drink reverse osmosis water you’ll be able to smell, feel and taste the difference.

     What Is The Best Reverse Osmosis System?

    Culligan’s Reverse Osmosis Systems are designed to bring your home safer, cleaner water you can rely on. Whether you want an endless supply of reverse osmosis water or a compact design that seamlessly fits into your home, we can help find the best filtration system for you.

    Aquasential® RO Drinking Water Filter System: Customizable to address your unique water issues, the Culligan Aquasential® RO is certified to reduce 60 contaminants and offers up to 7 filter options.* You’ll get an unlimited supply of cleaner, safer, great-tasting water for just pennies a glass.

    Aquasential® Tankless RO Drinking Water Filter System: This filtration system reduces dissolved solids in your water by up to 95% and provides over 600 gallons of cleaner, safer drinking water per day. You can rely on this system to deliver the quality water your home depends on without taking up extra space.

    Aqua-Cleer® Advanced Under Sink Water Filter System: With 13 advanced filter options designed to help solve multiple water problems such as lead, arsenic and chlorine, this is one of the most cutting-edge reverse osmosis systems in the industry. This smart filtration system is designed to address your home’s unique water needs, save space and blend in with your household as it features faucets that come in a variety of styles, colors and finishes.

    What Is The Lifespan Of A Reverse Osmosis System?

    The longevity of your reverse osmosis system will depend on regular servicing and maintenance. Upkeeping your reverse osmosis filtration system will require:

    • Routinely replacing parts that wear out, such as the storage tank
    • Filter changes and disposals
    • Regular maintenance

    Luckily, our Culligan Water experts are here to take care of everything for you. From delivery to maintenance, we ensure the longevity of your RO system and that all the parts are working properly. That means you can enjoy cleaner, safer, better-tasting water, while we take care of the rest.

    *Contaminants may not be present in your water.

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