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How an Alkaline Water Filter Works


As the protector of your home’s water quality, you know there are plenty of things to focus on, including taste, odor, appearance, possibly harmful contaminants and even problems with your plumbing.* However, there’s one more consideration you can’t see with the naked eye: pH level.

All water has a pH level, just like your own body. Unlike your body, though, your home’s tap water doesn’t have built-in mechanisms to make sure this pH level remains at optimal levels.Your water can have different’s positions on the pH scale, ranging from acidic to alkaline (or basic). 

Because water can have negative impacts on your home if its pH is too high or low, it’s helpful to know what your options are. Beyond the pH water level impacting your home, some people also seek out an alkaline filter because they believe alkaline water can bring certain health and flavor benefits.

Ready to monitor and change the pH level of your tap water with a solution like an alkaline filter? Here’s everything you need to know to do just that.

What is Alkaline Water?

The first step in controlling the pH level of your water is to understand what this measurement really means and why it matters. 

What Does the pH Scale Mean?

When you measure something’s pH, you’re finding its place on a scale that goes from zero to 14. The lower the number, the more acidic the substance. For example, pure water sits at seven and is considered neutral, while battery acid is at zero (acidic) and liquid drain cleaner is at 14 (basic or alkaline).

While pH water testing is best performed by experts, you can do an at-home test to get a very rough idea of what’s going on when you turn on the faucet. Just head to your local pet store and find litmus paper. 

Litmus paper is used to test the pH level of aquarium water — an important task, since different fish species have different needs when it comes to pH. When you put a drop of your tap water on a litmus strip, the paper will change color depending on acidity or alkalinity levels. You can use the same method to find the pH level of other substances in your home, giving you plenty of data to compare against. 

Remember, this process only gives you a general idea of your water’s pH level, but it does help you visualize the pH scale. It’s also a good exercise because it could help validate any odd flavors you may have noticed. For example, sour or metallic tasting water could indicate acidity that is too high, while a bitter or baking soda-like taste might mean your water is excessively alkaline.

How Does Water Become Alkaline or Acidic?

Because just about everything in nature has a pH level, there are constant chemical reactions happening in the outside world. Your water can be part of these reactions on its journey from the source to your faucet.

For example, say you have a private well. Although this well likely draws from a natural underground source called an aquifer, water may travel through various environments to get to the aquifer in the first place. Water often passes over rocks and other features along the way, causing it to pick up minerals like magnesium that impact the overall pH level. 

In many cases, pH levels are impacted by things outside your control. However, there are some ways to change the pH level of your water yourself, like an alkaline water filter pitcher or reverse osmosis system with an alkaline filter. You could also buy bottled alkaline water, although this can get expensive and the plastic water bottle waste can be harmful to the environment. In general, reverse osmosis systems tend to be more comprehensive, making it easy to access alkaline water while also improving your overall water quality. (More on that later.)

Is Alkaline Water Bad For Your Home?

There’s frequently a link between naturally alkaline water and hard water problems. That’s because the same minerals responsible for water hardness, including calcium and magnesium, can reduce water acidity. As a result, alkaline water may be associated with common hard water symptoms like limescale buildup, impacted water flow or reduced efficiency of water-using appliances. The good news is that this correlation is often specific to naturally occurring alkalinity — so an alkaline water filter won’t cause water hardness. 

Acidic water, on the other hand, can interact more directly with the pH level of your home’s plumbing system. If your water is highly acidic, it could corrode certain copper pipes and cause further reactions, possibly resulting in copper contamination of your drinking water.

The Science Behind Alkaline Water

Now that you know what alkaline water is, let’s find out why so many people want it in their drinking glass — and whether there’s solid science behind these claims.

Possible Benefits of Alkaline Water

For many, the word “alkalinity” suggests refreshing, invigorated water. That’s because alkaline water is often believed to have a wide range of health benefits due to the presence of beneficial minerals like magnesium. These alleged benefits include:

  • Digestive improvements
  • Metabolic improvements
  • Weight loss
  • Immune support
  • Superior hydration
  • Cancer resistance

Unfortunately, there’s not a lot of research or data to support such claims. Scientists and health experts are still debating the effect alkaline water has on human health, but for now, it’s smart to do your own research and stay wary of any promises that seem too good to be true.

Possible Drawbacks of Alkaline Water

Whether alkaline water is a miracle worker or not, one thing’s for sure: The pH level of your diet hasn’t been shown to cause adverse health effects. While extreme levels of alkalinity may cause dry skin or stomach upset and acidic water is sometimes suspected of causing acid reflux, there aren’t significant health risks associated with pH level variations for most people. However, for those with kidney disease, it’s especially important to check with a doctor before making choices regarding alkaline water.

The Final Word on Alkaline Water

Scientists have a lot of work to do before they can say for sure whether alkaline water is better for the human body. Until then, resolving the alkaline vs. acidic water debate comes down to your personal preference. Luckily, because alkalinity in drinking water is generally considered safe for most people, there’s no harm in trying an alkaline water filter to see what you think.

How an Alkaline Water Filter Works

Water isn’t always naturally alkaline, and even when it is, different environmental factors  like the presence of essential minerals can cause the pH level to fluctuate. This means that, if you’re interested in having alkaline drinking water, it’s best to consider an alkaline water system or sink water filter that supports alkaline remineralization. Why? Other solutions — like an alkaline water pitcher, alkaline water machine or bottled water with alkaline minerals — can be wasteful and generally less comprehensive in effectiveness, while a home water filtration system may be capable of adding alkaline minerals and reducing contaminants like heavy metals and chlorine at the same time.

Many alkaline water systems begin as water filtration systems. These best options for these water filter solutions utilize reverse osmosis (RO) to reduce contaminants. The process begins when water is highly pressurized and sent through a variety of initial filters, preparing it for reverse osmosis. Next, the water is forced through a reverse osmosis membrane, which filters additional contaminants. The final step involves additional specialty filtration stages — and the result is a cleaner drink of tap water.

After RO treatment, filtered water is generally neutral, which means it has an approximate pH level of seven (though this actual measurement can vary based on the pH level of your water initially). When you turn on the faucet, this water is exposed to open air, where it absorbs carbon dioxide (CO2). Unfortunately, CO2 can bring the pH level back down to between 5.5-7. 

The solution is to enhance RO water filtration systems with mineral boost cartridges. These cartridges become part of the specialty filtration at the end of the reverse osmosis process by adding back minerals that block some CO2 absorption. This can result in a moderate increase in pH that can enhance the taste of your tap water without causing hard water problems like limescale buildup in your plumbing.

Although a good RO water filter and alkalinity mineral boost cartridge combination can be a great solution, it’s important to note that the end result is dependent on the state of your incoming water; that’s because your water’s original pH level — acidic, neutral or alkaline — can change the outcome of your alkaline water filter process. For this reason, it’s often helpful to start by having a free, in-home water test that will tell you what to expect.

Do You Need an Alkaline Water Filter?

Everyone needs and deserves clean water — but that doesn’t mean everyone needs or wants alkaline water. At the end of the day, it mostly comes down to personal preferences rather than any proven benefits, so it’s up to you to decide.

Here are a few things to think about when considering alkaline water filters:

  • Taste: If the pH of your tap water is always fluctuating, it’s difficult to rely on a consistently crisp taste. An alkaline water filter helps make pH levels more predictable, allowing you to achieve a taste you love.
  • Health: For most people, there’s no health risk associated with trying an alkaline water filter. While the potential benefits haven’t necessarily been proven, this is your chance to see for yourself whether pH-invigorated water can make a difference.
  • RO filters: If you already have a reverse osmosis filter, it’s quick and easy to add an alkaline filter cartridge. If you don’t have one of these systems, you’ll need to have one installed first — but remember, reverse osmosis water filtration systems are great for reducing the presence of water problems beyond just pH, which means this might be a good opportunity to improve your water quality. 
  • Water hardness: Natural alkalinity can come with water hardness issues. A water softener can help address these problems, which is why water softeners and alkaline water filters can and should be used together.
  • Preference: In the end, the alkaline vs. acidic water debate is all about what you prefer. If you’re still unsure, consider an alkaline water filter that allows you to customize pH levels so you can try different tastes and decide what you like best.

Take Control of Your Water Quality

You work hard to make sure every glass of water is just right for yourself, your family and your guests. However, when unseen forces are at work — like the pH level of your tap water — you might be left wondering what your options are.

The good news is that pH isn’t beyond your control. All you have to do is brush up on a little basic chemistry and start learning what factors are influencing your water’s pH level. Once you have that information, it’s much easier to choose the appropriate solution — like a reverse osmosis water filtration system with an alkaline mineral boost cartridge (and maybe a water softener, too).

Remember, the first step is to find out what your water’s pH level is. You can do a rough test at home with a strip of litmus paper, but for the best and most accurate results, it’s best to call in the water experts.

Start taking control of your water quality today by scheduling your free water test.


*Contaminants may not be present in your water.

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