Is Reverse Osmosis Water Acidic? How To Test Yours

Is Reverse Osmosis Water Acidic? How To Test Yours

Anthony Barnes

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Reverse osmosis water is a popular way of purifying drinking water today, and it’s also one of the most misunderstood methods.

Many people have expressed concerns about the acidity levels of reverse osmosis water, questioning if it is actually acidic, and if so, why is it acidic, and is it safe to drink? 

Luckily, we are here to help. In this article, we will answer all of your reverse osmosis water-related questions. Read on for more!  

Is Reverse Osmosis Water Acidic? Is It Alkaline?

Reverse osmosis water is actually acidic, not alkaline.

When you think of the pH scale, then you will find reverse osmosis water sitting at a pH level of 6.5 on average, which is classed as acidic (with 7 being neutral and anything above 7 being considered alkaline.) 

However, this is no cause for concern.

The Environmental Protection Agency has stated that reverse osmosis water is safe to drink, so you can rest assured that drinking reverse osmosis water will not have a negative impact on your health. 

What Does “Acidity” Mean?

Acids are the exact opposite of alkalines, and they are defined by the pH scale.

Higher numbers on the pH scale are representative of higher alkalinity, while the lower numbers represent higher acidity. 

The pH scale works in a logarithmic way. This means that if you double a number, you get ten times the effect.

If you triple the number, you get 100 times the effect. So, this means that reverse osmosis water is actually 10 x more acidic than your standard, unfiltered water.

However, this is also no cause for concern, and you only have to check out the pH levels of other everyday foods and drinks to see why. 

For example, black coffee has a pH of 5, orange juice has a pH of 3, and lemon juice actually has a pH of 2!

These are perfectly safe to consume for the average person, so reverse osmosis water will be, too. 

Why Exactly Is Reverse Osmosis Water Acidic? 

According to science, acidic liquids can move hydrogen ions with ease.

If an acid is weak, like reverse osmosis water, then this happens very easily. Alkalines work in the exact opposite way.

If something is alkaline, then it will accept hydrogen ions a lot easier. 

So, reverse osmosis water will filter out alkaline mineral atoms like magnesium and calcium from the water, which makes it more acidic. 

Once again, you do not need to worry about these minerals being removed, as long as you ingest the recommended daily intake of these necessary minerals in some other way.

Luckily, the average person will get the majority of the necessary magnesium and calcium from their diet. 

Does Reverse Osmosis Water Have An Impact On An Alkaline Diet?

Is Reverse Osmosis Water Acidic? How To Test Yours

Does the acidity of the reverse osmosis water counteract the alkaline diet?

The alkaline diet is all about consuming lots of fruits and vegetables, with the aim of impacting the pH level of your blood and improving your health. 

The alkaline diet is not backed by science, and some scientists claim that while eating lots of fruit and vegetables has excellent health benefits, nothing you drink or eat will have a significant impact on the pH level of your blood.

This includes reverse osmosis water. So, drinking reverse osmosis water will not have a negative impact on your alkaline diet.

It is actually more true that you may do more damage to your body by not having a reverse osmosis filter for your water.

Sometimes, compounds like chlorine, arsenic, and lead, are very present in the drinking water in the USA, and all can lead to problems after long-term consumption.

The acidity of reverse osmosis water is merely a byproduct that is present as a result of removing these minerals from the water. 

How Can I Test The Acidity Of My Reverse Osmosis Water?

So, even though it is clear now that reverse osmosis water is not harmful, you may still want to check the acidity levels present.

There are four ways to do this, and they are all simple to carry out! Let’s take a more in-depth look! 

Test For Acidity With pH Strips 

pH strips are probably one of the easiest methods to test the acidity of your reverse osmosis water without any equipment.

You simply put the strip into the water, wait a few seconds, and then read the color of the liquid. 

It may be better to invest in a strip that is made specifically to test for pH levels within a certain range.

The pH levels of your reverse osmosis water are likely to fall somewhere in-between here.

These tests are better than broad tests because it can be difficult to tell the difference between the different hues and get an accurate reading. 

Test For Acidity With Litmus Paper 

Litmus paper functions in a very similar way to the test above. All you need to do is soak the litmus paper in the reverse osmosis water.

There are only two colors it can turn, and that is dependent on whether the pH levels are acidic or alkaline. 

However, it is important to note that litmus paper tests are less accurate than pH strip tests. Additionally, because reverse osmosis water is so weak in its acidity, the litmus test may produce no results. 

Test For Acidity At A Local Test Center 

Many cities in America have water testing services. You can usually find them at local government facilities or at universities.

They will analyze your reverse osmosis water for you and determine its acidity levels. 

This method of testing will produce the most accurate results compared to litmus paper and pH strips. 

Test For Acidity With Red Cabbage 

Think of this as a little bonus test, if you do not have access to any of the above three.

There is a pigment in red cabbage that will actually change in color based on the acidity level of your test subject – reverse osmosis water, in this case. 

All you need to do is blend the red cabbage piece with water (different water to reverse osmosis water).

After this, strain the liquid and remove the cabbage chunks.

Now, all you need to do is pour the reverse osmosis water through the liquid and stir.

If the water is indeed acidic, then it will turn red. 

Don’t forget that reverse osmosis water is very weak in its acidity, meaning any change won’t be too significant, though it will be slightly noticeable. 

Frequently Asked Questions 

Is Reverse Osmosis Water Acidic? How To Test Yours

What Is Reverse Osmosis And What Are Its Benefits? 

The reverse osmosis process is where water is forced through a membrane.

This causes the impurities to pass through the membrane while allowing the pure water to pass through.

Reverse osmosis is used to purify drinking water.

It removes contaminants such as chlorine, heavy metals, bacteria, and other chemicals from the water.

It also helps reduce the number of minerals and salts that are found in tap water. 

A great benefit of using reverse osmosis systems is that they help improve the taste of water and the water quality.

Many people prefer the taste of their reverse osmosis water over tap water. 

Should Reverse Osmosis Water Be Remineralized? 

You are able to remineralize reverse osmosis water, and this is a great way to minimize its acidity levels.

However, this is by no means necessary, and it is especially necessary for health purposes since reverse osmosis water is not harmful. 

How Do I Know Whether My Reverse Osmosis System Needs Maintenance? 

You should check your reverse osmosis system every month to make sure everything is running smoothly.

Here’s what you should look out for: 

• Check the pressure gauge. Make sure that it does not fluctuate wildly. Fluctuating pressure indicates that something is wrong with the unit. 

• Look for leaks around the faucet. Leaks indicate that something is wrong with either the plumbing or the unit itself. 

• Check the flow rate. If the flow rate is low, then this could mean that the unit needs maintenance. 

• Inspect the membranes. The membranes inside the unit must be clean. Dirty membranes may cause the unit to malfunction. 

Does Reverse Osmosis Water Take Minerals From You When You Drink It?

No. Reverse Osmosis water will not take essential minerals from your body. This process is reserved for drinking water.

However, some reports state that it will remove minerals such as calcium from the water, which is a mineral we need as part of our daily intake.

This is no cause for concern since as a general rule we get very little of the calcium we need from water, and most of it will come from our diets. 

Does Reverse Osmosis Water Cause A Vitamin D Deficiency? 

No. Reverse osmosis (see also ‘Reverse Osmosis Vs. Distilled Water‘) water will not cause a vitamin D deficiency. It has no effect on the vitamin D levels in the body.

Drinking reverse osmosis water will not cause the removal of minerals or nutrients. 

Final Thoughts

Reverse osmosis water has a pH of around 6.5, which does make it acidic.

Reverse osmosis water filters out alkaline chemicals from tap water that can be harmful, which is what makes it more acidic.

However, its acidity levels are not harmful, and they are actually closer to “neutral” on the pH scale than coffee, orange juice, and lemon juice. 

However, you may still want to test the acidity levels of your reverse osmosis water, and there are four ways to do this.

Choose between pH strips, a litmus test, taking your water to a testing facility, or using red cabbage to test its acidity.

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By Anthony Barnes

Anthony Barnes is the founder of Water Heater Hub and a second-generation plumber by profession. Before developing Water Heater Hub, Anthony Barnes was a full-time plumber, and he has undertaken a wide variety of projects over the decades. As a second-generation plumber, it was easy for Anthony to get used to the technicalities of all from a tender age