Advantages & Disadvantages of Reverse Osmosis (RO) Water

As more and more homes are installing reverse osmosis water filters there is one question that some people are concerned about – Is drinking RO water safe and healthy for their family instead of tap water? Does my family need to install a reverse osmosis filter? This article will take you on a journey to explore the truth about the pros and cons of RO water.

Reverse osmosis filter pros and cons

What is Reverse Osmosis

A physical filtration process called “Reverse Osmosis” uses extreme pressure coming from a high-pressure pump. This forces the water molecules to move against their natural osmotic gradient to pass through a selective semi-permeable membrane. The RO water transforms from a high-concentration solution to a low-concentration solution. The semi-permeable membrane filters out large-particle contaminants at the molecular level, achieving the separation of water and impurities. The reverse osmosis system goal is to deliver safe drinking water that is suited for home usage straight from the water faucet.

What is Reverse Osmosis Water?

RO water is a high-purity water that comes from a reverse osmosis system after the treatment process. Due to its absence of bacteria and contaminants, RO water is often used as clean drinking water for household purposes, especially for direct consumption, cooking, bathing, making coffee, and even for pet care.

Several pollutants are evident to be removed by 98% from water through reverse osmosis technology. This includes lead, asbestos, microorganisms, sediments, bacteria, fluorides, chlorides, sulfates, heavy metals, industrial chemicals, pesticides, and total dissolved solids (TDS), among others.

RO can effectively remove common ions from water:

● Sodium

● Magnesium

● Calcium

● HG

● Arsenic

● Chromium

● Selenium

● Radium

● Barium

● Cadmium

How Reverse Osmosis Water Filters Purify Your Water

The below diagram lets you understand how the whole house reverse osmosis system works.

How Does Reverse Osmosis Water Filters Work

The source water, such as seawater, well water, municipal water, rainwater, or river water, first passes through a pre-treatment system consisting of a sediment filter, GAC (Granular Activated Carbon) filter, and CTO (Chlorine, Taste, and Odor) filter.

The purpose of the pretreatment process is to use materials(quartz sand, activated carbon, and activated carbon fibers) to remove large particles, color, odors, suspended solids, viruses, bacteria, chlorine, and other contaminants from the source water. Simultaneously protect the reverse osmosis system. The water treated in this stage is known as primary treated water, suitable for general household use but not for direct consumption.

Next, the water that has undergone pre-treatment is propelled forward with the pressure pump, entering the reverse osmosis membrane under pressure. The reverse osmosis membrane has extremely high filtration precision, with pores as small as 0.0001 micrometers.

The water treated through RO is healthy, safe, and pure, and stored in a water tank for convenient access and direct consumption. Meanwhile, concentrated brine, also known as wastewater, is removed from the system through a separate wastewater pipe.

Reverse osmosis system for home

For households requiring higher quality of final product water, the system needs to be equipped with post-treatment devices between the RO faucet and the reverse osmosis tank. These are typically carbon filters or ultraviolet disinfection units. After passing through the post-treatment unit, the RO water has a better taste and is safer for consumption. After passing through the faucet, the final product water is suitable for direct household consumption.

What are the Benefits of Drinking Reverse Osmosis Water?

1)High Contaminant Purification Levels

The reverse osmosis water filtration system effectively removes 99% of contaminants in water, including harmful bacteria, viruses, heavy metals, and chlorine. The RO faucet can directly provide drinking water, ensuring highly pure water quality.

2)Better Taste

Reverse osmosis systems work wonders by stripping away minerals and impurities from water, resulting in a more revitalizing drinking experience.Using RO water in cooking ensures the taste and hygiene of food. RO drinking water systems are commonly used in hotels and restaurants to make coffee, tea, juices, and dishes. Additionally, RO water is odorless and colorless, fresher than tap water.

3)Reduces Waterborne Diseases

Waterborne diseases are caused by drinking contaminated water containing microbes or pathogens. Reverse osmosis water filtration systems can remove all such pathogenic microorganisms. Moreover, the semipermeable membrane can remove 99% of heavy metals such as lead, manganese, arsenic, and asbestos, making it safe to drink.

4)Good for the Skin

Soft water is gentler on the skin compared to hard water. Long-term use of RO water can keep your skin smooth and moisturized, reducing dryness and allergies.

Substances present in water


5)Energy-Efficient Alternative

Obtaining high-quality water typically involves high costs, such as with traditional distillation methods. Reverse osmosis water systems are more convenient and energy-efficient than distillation systems while providing comparable water quality. The cost of obtaining RO water is much lower than distilled water.

6)Widely Applicable, Especially in Water-Scarce Areas

For coastal, off-grid, and remote areas, obtaining clean, uncontaminated water is a luxury. Reverse osmosis water plants can be designed in different capacities and sizes according to customer needs, converting raw water such as seawater, rainwater, river water, and well water into potable water. In addition to household use, reverse osmosis technology is widely used in industries, municipalities, biopharmaceuticals, commerce, and the military.


Compared to bottled water, reverse osmosis water is both convenient and cost-effective. If you are currently purchasing bottled water for household drinking water, you will incur additional expenses each year.

The total daily water consumption for a household is approximately 100 gallons, with only 2-3 gallons used for drinking. Assuming the cost of bottled water ranges from $3 to $10 per gallon, the daily cost of purchasing drinking water would amount to $6-30. From a long-term investment perspective, even though the initial investment in a reverse osmosis water filter is higher, the annual savings can be considerable.

8)Reduction of Scale Accumulation

Reverse osmosis systems can remove calcium and magnesium ions that cause scale buildup, thereby softening hard water. Reducing TDS and removing chemicals will reduce the chances of corrosion, scaling, and mineral accumulation, thus saving energy. Softened water will not clog your pipes, coffee machines, faucets, and showerheads, extending the lifespan of household equipment and appliances.

Scale buildup caused by hard water

9)Environmentally Friendly

Reverse osmosis is a natural process that operates solely on physical principles, eliminating the need for chemical additives. As a result, it stands as an environmentally friendly solution, devoid of any pollution-causing agents. RO water replaces bottled water, reducing the pollution of plastic bottles to the environment.

Disadvantages of Reverse Osmosis

There are both pros and cons to reverse osmosis water treatment.

1)Flat Taste

It’s undeniable that RO (reverse osmosis) water is flat, without any taste. Because there are no dissolved substances or minerals in the water, some people may find it difficult to get used to this taste, making it a drawback of reverse osmosis water.

2)Good Mineral Removal

Before reading this article, you may have heard about the potential hazards of reverse osmosis water for the kidneys and health. Indeed, reverse osmosis water removes electrolytes such as sodium, calcium, magnesium, and potassium during the filtration process. So, is reverse osmosis water good for you?

If you are concerned about the electrolyte content in water, it’s best not to choose pure reverse osmosis water. Additionally, for individuals with poor kidney function, it’s better to avoid long-term consumption of reverse osmosis water. The high purity of reverse osmosis water may affect the kidneys’ normal function of eliminating excess minerals from the water. Lastly, some municipal water supplies add fluoride, which is beneficial for teeth, especially for children in preventing cavities. However, RO water doesn’t contain these fluorides.

3)High Waste Water Volume

The amount of waste water generated by reverse osmosis filters has always been a contentious issue. Typically, the waste water ratio of common RO filters in the market is 3:1 or even as high as 6:1. The waste water ratio refers to the ratio between the amount of waste water generated during the reverse osmosis process and the amount of pure water obtained.

This means that for every liter of pure water produced, there may be 3 to 6 liters of waste water generated, potentially leading to increased water bills. Although the wastewater to water ratio of some RO filters has been reduced to 1:1 or even lower.

Wastewater VS pure water produced by RO system

4)Slow Filtration Rate

During the reverse osmosis process, water is compelled to traverse through the tiny apertures of the reverse osmosis membrane to undergo filtration.  This filtration characteristic makes reverse osmosis filtration more meticulous but also slower compared to other methods. Moreover, reverse osmosis water purification systems come equipped with pre-filters and activated carbon filters. This contributes to extending the duration of the filtration process.

5)High Initial Cost

Reverse osmosis systems are advanced and efficient, thus they come with a higher cost, making the initial investment a significant expenditure for many households and businesses.

6)High Maintenance Costs

Even after installing an RO filter, regular professional maintenance and replacement of consumables are still required. The reverse osmosis membrane needs to be replaced every 1-3 years, while the first three layers of filter media are typically replaced every 3-6 months. If the reverse osmosis water filtration system is not regularly maintained and cleaned, the filtration efficiency of the reverse osmosis membrane may decrease, affecting the quality of the produced water.

7)Acidic pH of Water

Reverse osmosis water lacks alkaline substances such as minerals and soluble salts, so it may exhibit a slight acidity, with a pH usually ranging from 6 to 7. Acidic water may pose a slight corrosion risk to the pipeline system.

Can You Drink Reverse Osmosis Water Every Day?

The safety and suitability of reverse osmosis water for long-term consumption is a topic of concern for many readers. You can find various answers in forums and Google search results. The World Health Organization recommends against relying solely on reverse osmosis water for long-term drinking purposes due to its deficiency in essential trace elements and minerals that are beneficial for the human body.

However, it cannot be denied that the water we consume daily also carries some beneficial substances for our bodies. Nevertheless, the majority of minerals and trace elements needed by the body primarily come from the food we eat every day. Therefore, even if you drink RO water every day, its impact on your body is minimal. In comparison, the issues you should be more concerned about are the high chemical pollutants, TDS, soluble salts, and viruses found in tap water or well water.

Do I Need A Reverse Osmosis System?

Do I Need A Reverse Osmosis System

Whether you need to invest in a reverse osmosis system depends on the quality of your local water supply and your requirements for the quality of the produced water.

If your tap water is of good quality, meets drinking water standards, and has been inspected to be free of obvious impurities and odors, you can use it directly for drinking and daily life.

Additionally, water used for regular household purposes, agricultural irrigation, and livestock farming typically does not require high-purity water. Therefore, for these situations, you may not need to install a reverse osmosis filter. Instead, you may consider other types of water treatment systems that are more cost-effective, such as ultrafiltration systems, nanofiltration systems, or even simple water filters.

On the other hand, if you are dissatisfied with the current quality of your water supply and want to enjoy healthy and delicious water at any time, purchasing a reverse osmosis filtration system is a wise choice.

So,How to Remineralize RO Water?

Alkaline water does offer many benefits, such as improving digestion and maintaining the body’s acid-base balance. Even if you have installed a reverse osmosis filtration for your home, you can still equip it with an automatic mineralization system. An automatic mineralization system adds appropriate minerals, such as calcium and magnesium, to RO water.

To remineralize your water, simply purchase suitable equipment online based on your specific requirements. Alternatively, you can seek advice from water treatment service companies for more professional recommendations.

Is There Any Alternative Solution Better Than Reverse Osmosis?

If you are looking for the best way to get clean water at home, we still recommend using a reverse osmosis water filter as the simplest, most efficient, and advanced water filtration system. It improves taste while removing all other contaminants from the water.

If you need high-quality water for other purposes, you may also consider ion exchange, water softening, ultraviolet sterilization, ozone, and distillation methods.

The most cost-effective water filtration method is undoubtedly an activated carbon filter, suitable for situations where the raw water quality is already good. The filtered water can also be used for daily household use. Activated carbon filters have strong adsorption capabilities, enough to remove organic matter, odors, colors, pesticides, residual chlorine, and fine particles from the water. Moreover, activated carbon filters are easy to install, with minimal maintenance and installation costs. Most importantly, they do not produce excessive wastewater.

Final Words

After reading this article, you should now have a good understanding of the pros and cons of RO water. If you are still unsure whether an RO system is suitable for you and your family, entrust your water treatment needs to NEWater.

We specialize in providing the best RO purification systems, including under sink water filter systems, whole house RO systems, RO containers, laboratory reverse osmosis systems, and solar-powered seawater desalination RO purifiers.

You can start by testing your water. Our engineers will use their expertise to tailor a system specifically for you, aiming to provide the most cost-effective and durable water filtration solution, including equipment installation and maintenance. Our goal is to offer you access to healthy, safe, and fresh water anytime, anywhere at an affordable price.

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