How do alkaline water filters work?

water filter Alkaline water filter 7 min read

Alkaline water filters.. Should be a simple concept, right?

You put water into a water filter and you change its pH to something more alkaline, right?

Er.. yes.. but there’s more to know before any decision.

ALKALINE: A DEFINITION

The alkalinity of an alkaline water filter’s output can be indicated with a pH meter.

A pH meter provides a value as to how acidic or alkaline a liquid is.
The pH meter measures concentration of hydrogen ions in water.
Acids dissolved in water forming positively charged hydrogen ions (H+).

The greater this concentration of hydrogen ions, the more acidic the liquid may be.

Water Alkalinity or Acidity

Water is neutral at a reading of pH 7.
A lesser reading means the water is acid.
pH 6 is 10x more acidic than pH 7 and pH 5 is 100x more acidic than pH7.
A higher reading indicates alkalinity.

But wait! There’s more!

Yes, a pH meter can indicate alkalinity or acidity of water, but it is only an indication.
Other factors can affect the pH meter. But let’s go on.

Alkaline water contains alkaline minerals.

And yes, these minerals are:
a) in short supply in our modern diet, and
b)are all important in the balancing of our net acid levels, as well as many other health support functions.

So yes, we need alkaline minerals,

..and unless they are in our food, the only other regular source is the water we drink.
We can safely say that adding alkaline minerals to our diet will support our natural alkaline minerals buffer in our bloodstream. Its sole purpose is neutralisation of excess acid.

The Role of an Alkaline Water Filter

When we learn that our town water, containing acidic chlorine and chloramines, plus many other nasties, is actually adding to the acid overload in processed foods, sugars and carbs and metabolic stressors we ingest or create every day, it also makes sense that we should take advantage of alkaline minerals as we drink water.

Let’s take apart the alkaline water filter idea and see why people are paying up to $6000 to own one.

Introducing.. the alkaline water ionizer, AKA water alkalizer, AKA alkaline water filter.

This is the device one aggrieved author is upset about. He is a chemist. Here’s an excerpt:

As water molecules break down at the negative electrode to release hydrogen gas, they leave behind negative hydroxide ions. This is what makes a solution “alkaline.” Basically what this means is that as electrolysis proceeds, a dilute solution of sodium hydroxide (negative ions are always paired with positive ones) is produced around the negative electrode and can be drawn off as “alkaline” or “ionized” water. But you don't need an exorbitantly expensive device to produce a dilute sodium hydroxide solution. A couple of pellets of drain cleaner in a litre of water will do the job. So will a spoonful of baking soda. Of course these solutions will not produce any medical miracles. But neither will the posh alkaline water.

A water ionizer filters your tap water, then passes electricity through water, separating it into acid and alkaline streams.

Users drink the alkaline water, and the acid water (usually) goes down the drain.
Input and filter a litre of water from your tap, and you’ll get about half of the water out the other end with the original alkaline minerals in it.

ALKALINE WATER FILTERS: THE BIG QUESTION

Do you get more alkaline minerals as a result of drinking water from a water ionizer/alkaline water filter?

No. You get the alkaline minerals that were already in your water!
Which begs the question: if you buy an alkaline water filter/ionizer and your water is relatively alkali-free, can the water ionizer make it more alkaline?

No.. But it can make it look like it is more alkaline.

Remember earlier when I said that pH doesn’t necessarily reflect the amount of alkaline minerals in the water?

pH Test for alkaline water filter

Testing an Alkaline Water Filter for Alkalinity


A pH reagent test - can easily be deceived, and the easiest way to do this is to use exactly what the alkaline water ionizer uses: electrolysis.

Electrolysis affects the reading of a pH meter because it is reading the result of electrolysis instead of pure alkaline minerals in the water. It produces a dilute solution of sodium hydroxide - enough to quite radically affect a pH reading to make it look more alkaline than it really is.

So the person in a low alkaline water supply region is told to hit a button to boost the electricity that passes through their input water in their shiny new water ionizer, and lo and behold!

The pH meter or reagent shows a ‘healthy’ pH in the desired range of 8.5 to 9.5.

On the other hand, when a water supply is (as it is in vast areas of America, Australia and Europe!) already alkaline, the ionizer delivers the alkaline minerals already in the water, ‘repackaging them’ as ‘new and improved’ ionized water. If the water ionizer was set at the high voltage of the soft water area, then the readings on the pH meter would also be (falsely) high. (and the water may cause vomiting or diarrhea).

What if your tap water tests for perfect pH?
It has the required pH7.5 that all water facilities target, (using chemicals to balance whatever the source water may have been).

They add chlorine and chloramines that kill bacteria, but which also acidify the water. So they then add calcium carbonate to bring the acidity down.

There’s a big reason for this: acidic water sitting in old plumbing will eat away at joints, releasing lead and heavy metals. (Over 200 US cities have lead levels far beyond accepted health levels).

So... you pass your perfectly balanced water through your ($6000) ‘alkaline water filter’/ ionizer. If the water began its life as only slightly acidic, there will only be tiny amounts of alkaline minerals in it - just enough to balance the effect of the chlorine. And as we discussed earlier, your new ionizer will deliver that small amount of alkaline minerals into a separate stream, using electrolysis to create that separation.

And if you are disappointed with the pH.. well, as they will assure you.. it’s so simple to increase the electrical current and watch the pH soar.

Buffered Alkaline Water Filter vs. Unbuffered Alkaline Water filter.

Except.. the soaring pH does NOT reflect the true alkalinity of the water. It reflects the combined alkalinity of the water and the result of electrolysis. It is technically known as unbuffered alkaline water.

Unbuffered alkaline water is water that has little to no alkalinizing power.

If you have an electric water ionizer it's a simple test.
Add just a drop of acidic Vitamin C for instance, and it loses all its ‘alkalinity’.

Unbuffered alkaline water will virtually immediately be neutralised by acids in the mouth or stomach. Net result; zero.

Buffered water contains actual dissolved alkaline minerals. It is not artificially boosted in pH by electrolysis. These minerals, once ingested, join our own alkaline storehouse and suppl3ement, or top up our ‘bank’ of alkalinity with the ability to neutralise acids.

Try the acid drop test on a glass of buffered natural alkaline water: you’ll need a lot more acid to bring the alkaline water up to neutral pH7. It’s unfortunate that this small bit of irrefutable science isn’t talked about by electric ionizer vendors. It causes people like my quoted friend to get very angry.

Are Alkaline Water Filters Safe?

Yes. or at least they are as safe as the filtration method they employ.

Obviously the better the filtration, the safer the water. Strangely, big selling electric water ionizers have very basic filtration that does not address the newer contaminants we now find in our water, like fluoride, THM’s (Disinfection ByProducts), chloramines, heavy metals, viruses, bacteria, PFOAs..

Isn’t this what we should expect from any water filter, which of course includes alkaline water filters? Make a point of asking to see test results.

What pH should our water be?

It should be above pH7 to prevent leaching lead and heavy metals from pipes.
But from the healthy living point of view, it should be in the pH8.5 to 9.5.

pH Water Tests

We have a handy pH water test kit for people who want to know more about their own water.

After all, perhaps your water is already alkaline at the tap, in which case you’d be crazy to buy an electric water ionizer/alkalizer.

Want to know more?
~ The best countertop alkaline water filter they never talked about - until now. ~
The problem every electric water ionizer realizes they have after they pay the money.
~ The alternatives to paying $6000. Getting much more, for much less.
All this is a click away on the AlkaWay blog, or available via our monthly HealtheMail.

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