What Are The Disadvantages Of RO Water?

You may have heard about the benefits of drinking reverse osmosis (RO) water, but what about its downsides? In this article, we will explore the potential disadvantages of RO water and how they may affect your health and the environment.

From concerns about nutrient depletion to the wastage of water, we’ll uncover the lesser-known drawbacks of this popular purification method.

Health Risks

Loss of essential minerals

One of the main disadvantages of RO water is the loss of essential minerals. Reverse osmosis filtration systems are designed to remove various contaminants, including minerals such as calcium, magnesium, and potassium.

While this may seem beneficial for removing potentially harmful substances, it also means that the resulting water lacks the essential minerals that are necessary for maintaining good health. These minerals play a crucial role in proper bodily functions and are vital for maintaining strong bones, a healthy immune system, and normal cellular function.

Increased acidity

Another health risk associated with RO water is the increased acidity. The removal of minerals during the filtration process alters the pH balance of the water, making it more acidic.

Consuming water with an imbalanced pH level can have negative effects on your overall health. Acidic water can cause digestive issues, damage tooth enamel, and may even contribute to certain health conditions such as acid reflux or osteoporosis.

Waterborne diseases

While reverse osmosis effectively removes many contaminants, it is not foolproof when it comes to eliminating all forms of bacteria and viruses. In fact, RO systems are not specifically designed to remove microorganisms.

If the source water contains bacteria or viruses, there is a risk of these pathogens surviving the filtration process and potentially leading to waterborne diseases. It is important to note that proper maintenance, including regular disinfection and sanitization of the RO system, is crucial to minimize the risk of waterborne illnesses.

Environmental Impact

Wastewater generation

One of the notable environmental impacts of reverse osmosis systems is the generation of wastewater. RO filtration involves pushing water through a semipermeable membrane, with a significant portion of the feed water being flushed away as wastewater.

This can result in a substantial amount of water wastage, contributing to the strain on already limited water resources, especially in regions facing water scarcity. The generation of wastewater also means the consumption of additional energy to treat and dispose of it properly.

Energy consumption

Reverse osmosis filtration systems require electricity to operate effectively. The process of pushing water through a semipermeable membrane and creating the necessary pressure for filtration consumes a considerable amount of energy.

This reliance on electricity can result in increased energy consumption, adding to the overall environmental impact. Additionally, power outages can disrupt the filtration process, leading to the inability to access clean drinking water during such situations.

Water Wastage

Low water recovery rate

One of the major drawbacks of RO systems is their low water recovery rate. With traditional filtration systems, the majority of the input water is treated and becomes available for use.

However, in the case of reverse osmosis, the recovery rate is significantly lower, typically ranging from 25% to 75%. This means that for every gallon of clean water generated, a significant portion is wasted as wastewater. Such water wastage not only contributes to environmental concerns but also increases water bills for consumers.

Multiple filtration stages

Reverse osmosis filtration involves multiple stages of filtration, including sediment pre-filtration, carbon filtration, and the actual RO process. While each stage has its importance, the presence of multiple filtration stages can lead to a slower filtration process and lower water flow rate.

This can be particularly inconvenient when there is a higher demand for water, such as during peak usage hours. Additionally, more filtration stages may require more complex maintenance routines, further adding to the overall cost and effort required for operating the RO system.


Initial investment

The initial investment required for installing a reverse osmosis system can be relatively high compared to other options. RO systems typically involve the installation of various components, including a specialized faucet, a storage tank, and the necessary plumbing connections.

Additionally, professional installation may be required, further adding to the upfront costs. The expense of purchasing the RO system itself can vary depending on the brand, features, and capacity, making it important to consider the overall budget before opting for this method of water filtration.

Ongoing maintenance and filter replacements

Apart from the initial investment, the ongoing maintenance and filter replacements can also contribute to the cost of using RO water. Reverse osmosis systems require regular maintenance, including cleaning and disinfection, to ensure optimal performance and prevent bacterial growth.

Additionally, the various filters used in the system need to be replaced periodically to maintain the effectiveness of the filtration process. These filter replacements can add up over time, becoming an ongoing expense that needs to be considered before committing to a RO system.

What Are The Disadvantages Of RO Water?

This image is property of pixabay.com.

pH Imbalance

Reduced pH levels

Due to the removal of minerals during the reverse osmosis filtration process, the resulting water often has reduced pH levels. The loss of alkaline minerals can lead to a more acidic water pH, which can have adverse effects on taste, digestion, and overall health. Consuming water with a reduced pH level can disrupt the natural alkaline balance in the body, potentially impacting various bodily functions.

Impact on taste and aroma

The alteration of pH levels in reverse osmosis water can also have a noticeable impact on its taste and aroma. Many people prefer the taste of water that retains some minerals and has a slightly alkaline pH. RO water, however, may taste bland or flat due to the absence of these natural minerals. Additionally, the removal of certain minerals can affect the aroma of the water, further diminishing the overall sensory experience of drinking water.

Water Taste

Removal of natural minerals

One of the disadvantages of RO water is that it removes natural minerals present in the source water. While this may be desirable for removing contaminants, it can also result in water that tastes less appealing. Natural minerals in water contribute to its taste, giving it a refreshing and satisfying flavor. Without these minerals, the taste of RO water can be lacking in comparison, often being described as tasteless or even “empty.”

Residual taste of contaminants

While reverse osmosis systems excel at removing many contaminants, there can be instances where trace amounts of contaminants or their byproducts may still be present in the treated water. These residual tastes can be undesirable to some individuals, compromising the overall drinking experience.

The perception of residual taste can vary among individuals, with some being more sensitive to even trace amounts of substances, while others may not notice any difference.

Slow Filtration Process


Reverse osmosis filtration can be time-consuming compared to other water filtration methods. The intricate process of pushing water through multiple filtration stages and ensuring the appropriate pressure requires more time to complete.

This slower filtration process can lead to delays in accessing filtered water, especially during periods of high demand or when there is a need for immediate access to water. It is important to consider the time factor when opting for a RO system.

Lower water flow rate

In addition to being time-consuming, the multiple stages of filtration involved in reverse osmosis systems can result in a lower water flow rate. This means that compared to other filtration methods, such as carbon filters or pitcher filters, the amount of water that can be filtered per minute or per hour is relatively lower.

This can be inconvenient when there is a need for a higher flow rate, such as during activities that require a significant amount of water, or when multiple individuals are using water simultaneously.

Dependency on Electricity

Requires constant power supply

One drawback of reverse osmosis systems is their reliance on a constant power supply. The filtration process requires electricity to power the various components, including the pump and any additional features or monitoring systems.

Without electricity, the reverse osmosis system cannot function as intended, potentially leaving you without access to clean drinking water during power outages or in areas where electricity is not readily available. This dependency on electricity can be a significant disadvantage for those living in areas prone to power disruptions.

Impact of power outages

In situations where power outages occur, the functionality of a RO system is compromised. Unlike simple gravity-fed filtration methods, such as ceramic filters or carbon filters, reverse osmosis systems cannot filter water without the assistance of an electric pump.

This can be particularly concerning, as power outages can occur during emergency situations or natural disasters when access to clean water is crucial. It is essential to have a backup plan or alternative water sources in such scenarios to ensure a continuous supply of safe drinking water.

Limited Contaminant Removal

Inability to remove certain chemicals

While reverse osmosis is highly effective in removing a wide range of contaminants, there are certain chemicals that are not effectively eliminated through this process. Examples include volatile organic compounds (VOCs) and some heavy metals.

RO systems are not specifically designed to target these specific contaminants, and depending on the concentration and type of chemicals present in the source water, there may be limitations in their removal. If the primary concern is the presence of these chemicals, alternative filtration methods may be more suitable.

Selective filtration

Another limitation of reverse osmosis is its selective filtration capabilities. While it effectively removes many contaminants, it also removes minerals and salts that can have beneficial effects on health. The semipermeable membrane used in the RO process retains larger particles and contaminants while allowing water molecules to pass through.

This selectivity can result in the removal of desirable components and a reduction in water quality. It is essential to consider the specific contaminants of concern and ensure that a reverse osmosis system is suitable for addressing those specific needs.


Regular cleaning requirements

Proper maintenance is crucial for the optimal performance of a reverse osmosis system. The system’s components, including the filters, membranes, and storage tank, need regular cleaning to prevent the buildup of contaminants, scale, or bacterial growth. Neglecting regular cleaning can lead to a decrease in the system’s efficiency, potentially compromising the quality of the filtered water.

The frequency and intensity of cleaning will depend on factors such as the quality of the source water, the usage patterns, and the specific maintenance requirements of the RO system in use.

Potential for bacterial growth

If not properly maintained, reverse osmosis systems can become breeding grounds for bacteria. The presence of stagnant water, particularly in the storage tank, can create an environment conducive to bacterial growth.

This can potentially reintroduce contaminants into the filtered water, leading to health risks. Regular disinfection, proper cleaning, and adhering to manufacturer guidelines are essential to minimize the risk of bacterial growth and ensure that the water remains safe to drink.

In conclusion, while reverse osmosis water filtration systems have their benefits, it is important to consider the potential disadvantages before making a decision. Loss of essential minerals, increased acidity, and the risk of waterborne diseases are health risks associated with RO water.

The environmental impact includes wastewater generation and energy consumption. Water wastage, cost, pH imbalance, water taste, slow filtration process, dependency on electricity, limited contaminant removal, and maintenance are other factors to take into account. Understanding the full picture will help you make an informed decision about the suitability of reverse osmosis water for your needs.