7 Common Myths About Reverse Osmosis

Reverse osmosis (RO) systems are one of the most popular forms of filtration. Because of their popularity, they are the victim of conspiracies that are misinformed, misguided, or simply not true at all. Despite false rumors, RO systems are one of the best residentially available filtration systems because they suit many households’ needs. Below you can find information about common reverse osmosis myths and what makes them valid or invalid.

What is reverse osmosis?

Reverse osmosis is a common filtration method that reduces the levels of many contaminants in water. Water is placed under pressure and passes through a semi-permeable membrane. The membrane contains tiny pores that block contaminants from reaching the less concentrated side. Once the contaminants are filtered out, they are washed away with excess water. The filtered water enters a storage tank, where it is kept until the attached faucet opens.

Reverse osmosis systems come equipped with at least three stages, each one specializing in filtering out different contaminants. The three minimum stages of a reverse osmosis filter include a sediment and carbon prefilter, a reverse osmosis membrane, and a carbon postfilter. Additional in-line filters can be added, like a carbon postfilter to further reduce chlorine levels in water, or a remineralizing filter to add alkalinity back to the water. Other systems employ multiple pre-filters to help protect the membrane and prolong its lifetime. In areas with hard water, a water softener should be added before water enters the RO system to prevent minerals from causing damage to the RO membrane. If you are relying on a well for your household’s water, you should make sure you have appropriate disinfection pre-treatment before the RO system, like UV Purification.

7 common reverse osmosis myths

1.  Reverse osmosis water is unhealthy to drink

One of the most common myths about reverse osmosis water is that it is unhealthy to drink because of the lack of minerals left after filtering. Some people even believe that RO water leaches minerals out of your body. However, the claim that reverse osmosis water is unhealthy is false. One should not rely on water alone for mineral intake. Rather, minerals should be absorbed by eating a balanced diet that includes necessary nutrients. Many minerals are not able to enter your bloodstream via liquid. Instead, they must be absorbed by plants and converted to a usable form. These usable minerals can then be absorbed by consuming these plants. As a result, the best way to reach your mineral intake goals is a balanced diet followed by clean reverse osmosis water. Water alone does not contain enough minerality to provide nutrition.

2. Tap water is just as good as reverse osmosis water

While city water treatment has standards it must adhere to, these standards do not make water ideal for consumption. Water treatment plants, just like everything, are bound by monetary restrictions. For every contaminant present in water, there is an ideal level of contamination and there is a realistic level that mass treatment can yield. Lead, for example, is dangerous to consume at any level of concentration. However, to completely eliminate lead from water, city water treatment plants would need to spend far more money than is possible, so the EPA must set realistic standards that toe the line between long-term health and monetary feasibility. Since lead cannot be completely eradicated during water treatment, the EPA standard for lead in drinking water is 15 parts per billion. While this may seem like an inconsequential amount of lead, it can lead to long-term health effects, especially in pregnant women and young children. Installing an RO system will not only make your water taste better, but it will also reduce levels of contaminants, such as lead, that can compromise long-term health.

3. Bottled water is better than reverse osmosis water

Not only is the quality of reverse osmosis just as good, if not better, than bottled water, but it is also much more environmentally friendly. Many brands of bottled water use reverse osmosis as their filtration process. The differing tastes of these brands rely on the minerals added back to the water after filtration. Since it uses the same filtration process as many bottled water brands, a home reverse osmosis system can taste just as good as bottled water. From an environmental perspective, home RO systems do not produce nearly the amount of plastic waste that water bottles do. Around 60 million water bottles are wasted in the U.S. every day, leaving behind a massive carbon footprint. Of those 60 million, about 12 percent are recycled. Even the plastic that is recycled cannot be reused in applications like food packaging. Reverse osmosis systems help massively reduce plastic usage in homes every year and, since they cost little to maintain, are much more cost-effective than bottled water.

4. Reverse osmosis filters are expensive

While reverse osmosis systems are not inexpensive, they are much cheaper and more eco-friendly than relying on bottled water. Point-of-use RO systems, which are much more common than whole-home systems, range from $150 to $1300. In contrast, a single person can expect to spend about $1500 on water bottles annually. Contrary to purchasing bottled water, a reverse osmosis system is a one-time purchase. While replacement filters must be purchased annually, their cost does not come close to the price of bottled water.

5. Reverse osmosis is wasteful

While reverse osmosis systems must expel water in the filtration process, their efficiency has improved drastically in the past couple of decades. The term wasteful is misleading because reverse osmosis systems utilize the “wasted” water rather than dispensing it without use. When you take a shower, wash your dishes, or wash your clothes, you do not consider the water you used in those processes to be wasted. Rather, you used it to benefit the health and well-being of yourself. The same can be said for reverse osmosis systems. To appropriately filter water for consumption, some water must be used to carry contaminants away from the system.

Most household reverse osmosis systems use about 4 gallons of water for every gallon of filtered water produced. Some factors, such as low water pressure and lack of maintenance, can cause RO systems to be less efficient. Ensuring that your water pressure stays above 50 PSI will help you get the maximum performance out of your RO system. Regular maintenance will also go a long way in preserving your system. While RO systems are low maintenance, their filters should be replaced about once a year with the exception of the RO membrane, which should be replaced once every 2 years.

You can also enhance your reverse osmosis system with a permeate pump. Permeate pumps boost the performance of a reverse osmosis system by preventing water pressure in the storage tank from pushing against the RO membrane. This leads to less wastewater and improves the environmental friendliness of your system.

6. Refrigerator filters are just as good as reverse osmosis filters

Refrigerator filters are excellent at enhancing the taste of water, but they do not remove nearly as many contaminants as a reverse osmosis filter. Fridge filters use an activated carbon core that mainly removes the foul taste and odor of chlorine and chloramine. Reverse osmosis filters, on the other hand, feature at least three stages: a sediment/carbon prefilter, a reverse osmosis membrane, and an activated carbon postfilter. They are also often used with water softeners to remove hardness from the water before it enters the reverse osmosis filters or other whole-house treatment systems like UV Purification. Not only will reverse osmosis systems reduce chlorine levels, but they also reduce levels of total dissolved solids, salts, sediment, arsenic, volatile organic compounds, and many other types of contaminants. Refrigerator filters will enhance the taste of your water, but they will not remove these contaminants.

7. I will use a water softener instead

Water softeners are often used to soften water before it enters a reverse osmosis system because hard water can cause scale buildup in an RO system that shortens its lifetime. Not only does hard water affect reverse osmosis systems, but it also deteriorates plumbing and appliances that use it. While water softeners are great for softening water, that is the extent of their usefulness. If you live in a state that is prone to hard water, such as New Mexico, Utah, Wisconsin, Indiana, Florida, and the western half of Texas, a water softener is essential in elongating the lifespans of your appliances and plumbing. However, water softeners do not take the place of a proper water filter.

A water softener is not meant to make water healthier to drink. Hard water is not unhealthy to consume, but it can cause havoc on its way to your faucet. An RO filter, on the other hand, is designed to make water safe to consume. Instead of removing hardness minerals, it removes contaminants, such as lead and arsenic, that cause bodily harm over time. As a result, a water softener cannot be used as a replacement for a reverse osmosis system. However, if you live in a region with hard water, a water softener is needed to maintain the health of your RO system, appliances, plumbing, and skin and hair.


Posted by 
John Woodard on July 02, 2022

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