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Reverse Osmosis

What Is Reverse Osmosis & How Does it Work?


What Is Reverse Osmosis & How Does it Work?


If you want to take your water filtration system to the next level, look no further than reverse osmosis (RO). You may be scratching your head right about now, wondering, “What is reverse osmosis, and what does it have to do with my water?” We’ll explain how it works and explore the benefits of reverse osmosis water.

What Is Reverse Osmosis Water?

Unlike other kinds of water – like mineral water – reverse osmosis water is not defined by what it does or doesn’t contain. The term also does not describe water with a particular taste or texture, as is the case with sparkling water.

Instead, reverse osmosis water is simply water that has been treated with an RO filtration system. Because of this process, reverse osmosis water tastes pleasant, and it can be much cleaner than regular tap water.

Some of the water sold in stores in single-use plastic bottles are treated using reverse osmosis processes alongside other filtration techniques. However, reverse osmosis water most frequently refers to drinking water that’s treated at the point of use (say, from your kitchen sink).

In these instances, reverse osmosis water is available on demand, straight out of a faucet. You can use it for drinking or cooking, and it tastes great right from the tap without negatively affecting the flavor of food or beverages.

How Does Reverse Osmosis Work?

One of the most common uses for the reverse osmosis process is desalination, which is the process of removing salt from seawater to make it safe to drink. However, reverse osmosis is also capable of treating your household drinking water at the point of use. 

how do reverse osmosis systems work

So what does reverse osmosis mean?

Reverse osmosis happens when pressure is applied to a highly concentrated solute solution to force it across a semipermeable membrane that keeps undesirable components from passing through. This process leaves a higher concentration of solute on one side and only the solvent on the other. In the example of using RO for desalination, the solute would be salt, and the remaining solvent is freshwater.

All in all, this means that reverse osmosis leaves you with water that’s more suitable for drinking.

Whether treatment takes place at a sink in your kitchen, bathroom or elsewhere, the same RO method can be applied to help remove other minerals, substances and potential contaminants from your drinking water.* 

In a typical reverse osmosis water filtration system, water first flows through a pre-filter to remove larger sediment, such as sand or dirt. Then, it passes through an activated carbon filter, which reduces unpleasant tastes and odors from issues like chlorine in your water.

In the actual reverse osmosis stage, water flows across a tightly woven membrane that separates the water from contaminants as small as a single atom. This phase can reduce up to 95% of total dissolved solids in your water. Advanced RO products may also include additional filtration stages depending on the system and the user’s needs.

Is Reverse Osmosis Water Better for You?

Reverse osmosis filtration doesn’t just provide you with great-tasting water. It also can help ensure that the water your household depends on is cleaner and safer.

Reverse osmosis can minimize the presence of many possible contaminants that may be found in tap water, like lead, lead, mercury and chromium.* That said, the reverse osmosis stage on its own has a greater impact on the concentration of some substances than others.

What Is Not Removed by Reverse Osmosis?

While multistage reverse osmosis systems can reduce contaminants such as chloramine, volatile organic compounds (VOCs) and so-called forever chemicals (like PFOS and PFOA), this filtration doesn’t take place specifically in the RO stage of filtration. That’s why advanced reverse osmosis systems are designed to address these potentially harmful components through the use of additional filtration layers beyond the standard RO phases. One example of such a filter is Culligan’s Total Defense cartridge, which is certified to reduce contaminants such as mercury, chloramine, VOCs (volatile organic compounds), PFOA/PFOS and more.

The bottom line is this: If you’re looking for peace of mind regarding the water you and your family consume every day, the advanced, multistep filtration offered by reverse osmosis systems can provide the help you need.

Is It Healthy To Drink Reverse Osmosis Water?

According to the Water Quality Association, drinking RO water does not pose any health risks.  Reverse osmosis processes can help reduce the presence of potentially harmful substances that are sometimes found in tap water, while additional filtration stages may be deployed to help address additional concerns. If your water contains harmful substances like lead, for example, RO can make your household water supply safer to drink and better for you. 

How Does Reverse Osmosis Compare To Other Water Treatment Options?

Reverse osmosis isn’t the only way to treat your drinking water. However, it’s one of the most powerful options available for treating an impressively wide range of issues. Not only that, but under-sink RO systems ensure that you have cleaner, great-tasting water on demand whenever you want.

Compare this to other options like tap water filters or filtered pitchers. Tap filters bring a similar convenience factor (you won’t have to go and purchase single-use bottles of water), but the filtration technology is fairly limited in what it can accomplish. Similarly, basic filtered pitchers that require repetitive re-filling and slow filtration may reduce the impact of chlorine on the flavor of water, but they won’t help you with issues like viruses, bacteria, fluoride, nitrates and others.

High-volume, comprehensive systems such as RO are the best options for ensuring your water is cleaner, safer and great tasting.

Get a Water Test To Determine Your RO System Needs

If you think your family could benefit from a reverse osmosis system, the first thing you need to do is to test your water to find out what specific issues you need to address. (It’s also recommended that well water users have their water tested at least annually, and you should always conduct testing if you’ve moved to a new home or noticed changes in your water.)

Even if you think the taste and quality of your water have been consistent for a while, you might decide you could use an upgrade. After all, you may be able to get used to strange-tasting water, but you shouldn’t have to. More importantly, not all problem water issues can be seen, tasted or smelled, so testing is still a crucial step.

It will help you zero in on the appropriate treatment options for your particular needs. Working with a professional to understand exactly what’s in your water can help you discover the best treatment option.

Culligan Reverse Osmosis Filtration Systems

The best reverse osmosis system for your home will depend on your water use patterns, space requirements and budget. Culligan applied its more than 85 years of water treatment expertise to develop innovative, proprietary RO filtration technology. We’ve incorporated this technology into a variety of reverse osmosis systems designed to offer flexibility and uncompromising quality.

Take a look at some of our options below. Note that RO systems are typically installed under the sink, though some can be installed in the basement where it makes sense. 

  • Aquasential® Smart Reverse Drinking Water Filtration System: The Aquasential Smart RO is certified to reduce 58 contaminants and offers up to 7 stages of filtration and 12 filter options. Smart technology lets you track water consumption and contaminants reduced. You can also see cost savings and bottles saved from reduced use of single-use plastic water bottles.
  • Aquasential® Reverse Osmosis Drinking Water System: Get a virtually unlimited supply of cleaner, safer water with a system that’s customized to your home’s specific water needs. Certified to reduce 60 contaminants, the system is designed for easy setup and maintenance. An optional monitor light on your faucet can indicate when it’s time to change filters, which can last up to two years.
  • Aquasential® Tankless Reverse Osmosis System: The unique tankless design delivers the quality water your home depends on without taking up extra space under your sink. The filtration system reduces dissolved solids in your water by up to 95% and provides over 600 gallons of cleaner, safer drinking water per day. 

What Kind of Maintenance Is Required With a Reverse Osmosis System?

As with any water filtration system, RO systems need periodic maintenance to continue operating at peak performance. The Water Quality Association notes that routine upkeep for reverse osmosis solutions includes replacing pre-filters, post-filters and RO membrane modules. With Culligan reverse osmosis drinking water systems, you have the option for a filter life of up to two years. Additionally, smart sensors can let you know when components need to be replaced, so you’re not removing them too soon or too late. Many local Culligan dealers also offer ongoing service programs that make maintenance easy and hassle free.

Do I Have To Buy an RO System Upfront?

If you think a reverse osmosis system is the best way for you to treat your drinking water at home, it’s important to consider your financial options.

Fortunately, buying an RO system from a supplier outright isn’t the only way to go about it. If you rent your home or want to try out a reverse osmosis system first before you commit to purchasing one, many suppliers will offer you the option to rent a system. Some rental agreements even include bundled maintenance and support. You may also be able to explore rent-to-own options if you want to give your RO system a trial run first. (Check with your landlord ahead of installing any systems.)

Additionally, if you know that owning a reverse osmosis system is in your future, you may be able to explore financing options with your provider. That way, you can start to enjoy great-tasting water quickly while completing payments for the system over time.

Reverse osmosis systems are an attainable solution for households with a wide variety of needs, from longtime homeowners to first-time renters on a budget. Work with your supplier to discuss not only which solution is right for you, but which payment options fit your needs best.

Reverse Osmosis Water: A Step Forward for Your Drinking Water

Reverse osmosis is one of the most effective ways to broad treat your water, allowing you to address a wide range of potential contaminants and impurities in your home’s drinking water. Reverse osmosis filtration can help provide peace of mind for your family – for today and tomorrow.

Your home’s specific water filtration needs will depend on what’s present in your water, as well as the taste, odor and quality issues you want to address. To learn more about your home’s water quality – from water hardness to the presence of undesired chemicals – scheduling a water test is the first step.

*Contaminants may not necessarily be present in your water.

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