remove limescale from tap water

How to remove limescale from tap water?

Limescale in tap water can be a big problem. Coffee machines and kettle get clogged up, glasses get tinted and difficult to clean and sometimes even the faucets and shower heads get blocked. Therefore many households are looking for ways to remove limescale from tap water. In this article we will explore what limescale is, potential health issues with limescale, types of limescale filters and the best alternative to filter limescale.

What is limescale in tap water?

Limescale is actually the result of hard water. Hard water is filled with minerals including calcium, carbonate, magnesium and manganese. When scale deposits are showing on your coffee maker, tea kettle, carafes and water glasses there is probably a “hard” problem in your home. Statistics reveal that 85% of European and similarly 85% of US homes are affected by such issues. Limescale is that hard, chalky residue that lurks inside your taps, pipes and even kettle, left behind by hard water that contains above average levels of dissolved minerals (TDS). And while hard water and limescale isn't dangerous, it could be very annoying and contribute to poor taste.

Is limescale in tap water bad for you?

Generally the calcium and magnesium that makes up limescale is not unhealthy. Limescale, in normal tap water quantities is therefore not bad for your health either. On the contrary: most mineral waters you find in stores have minerals like magnesium and calcium that are good for your body. The daily recommended minimum intake of calcium is 500-1200mg and magnesium 300mg. If you drink two liters of water a day, you could be getting 10 to 20% of your daily calcium requirement. Even more importantly you get up to a third of your required magnesium from tap water.

What about hard tap water?

Hard water is the result of high mineral content which usually includes calcium and magnesium. It has no known adverse health effects. WHO says that in addition, hard water, particularly very hard water, could actually provide an important supplementary contribution to total calcium and magnesium intake. There is some evidence from epidemiological studies that magnesium or hardness has a protective effect on cardiovascular mortality. At the moment the evidence is being debated and does not prove causality. There may also be health conditions where the patients should probably avoid hard water including those with kidney stones. But once again the science is inconclusive.

How do I remove the limescale from tap water?

There are several methods to remove limescale from tap water including

A) remove the calcium and magnesium ions from the water, so that calcium and magnesium carbonates cannot form

B) remove the calcium and magnesium entirely

C) prevent calcium and magnesium ions from forming calcium and magnesium carbonates

Method A: Ion Exchange Water softeners using e.g. ion exchange resins, swap the calcium ions for sodium ions. This is why the water becomes salty. Water softeners typically separate out the calcium and magnesium ions as waste water. Ion Exchange generally uses cation resins that are strong acid/strong cation (SAC) resin beads to reduce hardness levels and increase sodium levels by removing scale-forming calcium (Ca2+) and magnesium (Mg2+) ions. The downside is that the removal process can make the water slightly acidic (like naturally soft water). This can sometimes take a few weeks to get used to if you have been drinking hard water all of your life. Method B: Reverse Osmosis (RO) Uses a membrane with tiny holes to push through the “pure” water and block other chemicals such as calcium, magnesium, lead and more. Read more about Reverse Osmosis Filters. This is effective in removing limescale but also removes all the healthy minerals and makes the water taste "flat". Method C: TAPP Water Our proprietary limescale inhibitor forms a complex with inorganic contaminants and prevents them from forming hard scale, staining, etc. It forms a protective coating of insoluble mineral scale in the coffee maker, kettle, water pitchers, etc. The upside is that Calcium and Magnesium does not get reduced and the water doesn’t taste salty. The slight negative side is that you may still see some bubbly white particles in your tap water. Other: Magnetic / Catalytic / Ionization Devices for limescale removal: These are magical magnets sold in hardware stores and on social media that claim to soften the water with the magnetic force. Lab testing of these devices have generally shown that they don’t work.

What does TAPP Water use to remove limescale from tap water?

TAPP 2 Limescale Filter TAPP Water spent the past 4 years experimenting with different technologies to come up with the best mix between taste, scale removal effectiveness and capacity. To ensure the highest efficiency of limescale removal EcoPro and EcoPro Compact uses the latest technology available for limescale reduction. The technology combines on our 5-stage microfiltration carbon block technology with a proprietary formula for scale reduction by sequestering the calcium and magnesium minerals which cause limescale and corrosion. At TAPP Water we are water geeks and believe in total transparency. We study everything there is to know about water quality, contaminants, filters, health benefits and issues related to drinking water in the markets where we are active. Best of all, we share everything we learn with you here. See our Independent Lab Tests for results on limescale reduction with our filters.

What are the benefits of a limescale water filter?

If you live in an area with hard water and limescale the benefits of limescale water filter include:
  • No more limescale in the coffee pot or tea kettle
  • No more limescale in carafes and glasses making them difficult to clean
  • Potentially better tasting coffee, tea and drinking water if you are used to soft water
  • Your Nespresso machine, other coffee makers and appliances that require water may last longer and require less maintenance


In summary
  • Limescale is the result of hard water formed by calcium and magnesium
  • There is no proven negative health impact of hard water or limescale
  • There are various filter technologies available for limescale removal in tap water including Water Softeners, Reverse Osmosis, Ion Exchange and TAPP Waters proprietary technology
  • EcoPro, EcoPro Compact and PitcherPro uses the latest combined water filtration technology to keep your tap water free from limescale


Min daily intake of calcium for adults: Min daily intake of magnesium for adults: Health impact of hard water: How Ion Exchange (IX) works:
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