Calmat Electronic Anti-Scale Water Softener & Treatment System Review

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The Calmat is an electronic anti-scale water treatment system that makes use of capacitive impulse technology to change the crystallization process of liquid calcium in hard water, so that it loses its adhesive power and cannot stick to surfaces anymore.

To be more precise, the system generates dynamic high-frequency electronic impulses that are transmitted into the water.

This causes calcium crystals to form into a rod-like structure. These crystal rods are held in suspension and washed away with the water as a fine powder.

Of course, the goal is to protect a house’s plumbing system and water appliances against scale deposits.

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Tech:Electronic Water Descaler
Made in Germany:

Our Rating

Calmat Electronic Anti-Scale Water Softener – Key Features

Apart from preventing scale, the Calmat also prevents rusting.

How? Due to the treatment, tiny amounts of carbonic acid are released in the water.

This slowly reduces existing limescale and rust deposits, however, a protective layer remains in the cleared metal pipes.

FYI: Carbonic acid is a natural scale solvent.

What’s more, the Calmat cannot be compared to the cheaper magnetic water conditioners, which we are not 100 percent certain if there even is real scientific evidence that proves that they actually work.

Calmat is not magnetic-based, which also means that it’s  suitable for all pipe materials. The maximum pipe diameter is  1½” – ideal for single-family houses.

Just note that iron content in your water should not exceed 1 ppm. The same goes for manganese, which should not exceed 0.1 ppm.

Calmat Pros

There are a couple of benefits that the Calmat descaler provides. The most important ones are:

  • Eco-friendliness – No chemicals or salt are used in the conditioning process. This means that you don’t get provided with water with excessive sodium content making it safe(r) for consumption. It also means that nothing is released into our water supply systems and eventually the environment.
  • Healthy – All healthy minerals are preserved in the water.
  • Save a fortune – The electronic impulse descaler allows you to save a fortune by not having to spend as much time and money on costly repairs and maintenance of your home’s plumbing system and appliances. You can also make considerable savings on washing and cleaning agents.
  • Low electricity consumption – The low electricity consumption is another reason why the Calmat is so eco-friendly. Your energy bill will remain more or less the same. According to the manufacturer, the costs amount to approx. $4 per year.
  • Made in Germany – Speaking of the manufacturer, the Calmat is made in Germany by a small family-run business.
  • 5-Year Warranty – An international warranty is granted for all Calmat units world-wide.


The Calmat – learn more on

Installation + Startup Instructions

Don’t worry, the unit is very simple to install with no tools or plumbing needed.

You should note, however, that the box is not weather proof.

Also, the manufacturer recommends to install the unit downstream of any whole house water filtration system. Here’s how:

If a softener is not equipped with a bypass valve, we recommend you provide for one for ease of maintenance. Also, make sure to comply with local plumbing codes.

  1. Place the unit on the main water line and fix it with cable ties (included). This can be done horizontally or vertically – whatever you prefer. You can also mount it on a wall.
  2. Insert the red impulse cable into the left socket.
  3. Remove any casing or insulating material from your desired pipe section.
  4. Route the cable to the pipe and fasten it with a cable tie.
  5. Tightly wind the cable around the pipe so that it looks like a coil.
  6. Plug the second impulse tie in the black loop at the end of the cable and fasten it.
  7. Follow the same steps for the second impulse cable. Both cables can also be wound on thicker connection pieces, such as couplings.
  8. Connect the adaptor to the electronic unit with the socket on the left side of the device.
  9. Plug in the power socket.
  10. Check if the green control light illuminates.

The Package (Parts)

  • Electronic unit
  • Power adapter
  • 2x impulse cable, copper
  • 8x cable binders
  • Instruction manual
  • 1 warranty card
  • Switching adaptors, UL and TÜV approved

Programming, Settings & Maintenance

Usually, once you’ve set up the Calmat water descaler, it’s totally maintenance-free. So all you need to do is choose your language and select the program according to your pipe material and diameter.

The only exception is when scale breaks loose in small chunks that ends up in the valve of one of your faucets. In this case, the valve needs to be removed and cleaned out.

We know, this means additional work on your part, but it’s a clear sign that the Calmat is doing its job.


You can download a manual for this product here: Manual

Calmat Cons

Nothing so far. Just be aware that it may take up to a few months to see the desired results – think reduction of scale deposits – says the seller.

Calmat Review: Our Verdict

For all we know, it looks like this thing really works.

The majority of customers report that the Calmat electronic anti-scale water treatment system has exceeded their wildest expectations, with no more stains on dishes and no scale on bathroom fixtures for example.

And taking into account that this device is more affordable than any regular salt-based water softener, we give it a thumbs up and rate it with 4.5 stars!

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This completes our Calmat electronic anti-scale review. If you have any questions, please don’t hesitate to leave a comment below!

About the Author Gene Fitzgerald

Gene Fitzgerald has been with BOS since the very beginning. She is head of content creation and has fully immersed herself into the home water treatment industry only to become an expert herself. Outside of BOS, Gene loves reading books on philosophy & social issues, making music, and hiking.
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Leave a Comment:

Les says January 7, 2019

This product does nothing I’ve had now 6 months hasn’t improved anything.

    Gene says January 7, 2019

    Hi Les,
    Thank you for your comment. Maybe there’s too much iron/manganese in your water?

Gaetano Buttaro says February 8, 2020

My Iron content is less the 0.04 Mg/L and there is no reference to Manganese but the Magnesio is 4,7 Mg/L.
I assume that Magnesio is Magnesium, not the same as Manganese correct? Also will this take care of the entire house or is there a pipe length limit?

    Gene says February 10, 2020

    Hey Gaetano,
    Sorry, never heard of Magnesio. Magnesium and Manganese are two different elements, correct. Should work for the entire house, but better check with the manufacturer!

Andrew Chen says October 31, 2020

I have installed the Calmat on my water pipe just as it enters the house. From that point in goes into my water softener which is still in operation. Is this set up Okay to run both at the same time?

    Gene says January 6, 2021


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