Choosing a water filter should not only be about taste but how effective it is at removing unwanted contaminants. While improving the taste is important to the enjoyment of drinking water, the removal of contaminants that are invisible to the eye is perhaps more important from a wellbeing point of view.

When people invest in a water filter they are making an investment in their own health. The everyday benefits of drinking clean, fresh water every day are undoubted. Yet the type of water filter you choose will determine how it works and the effect that has on your drinking water.



To properly filter contaminants of all types water filters need to combine more than one approach, meaning the more powerful and comprehensive the water filter is, the better it will perform.

Not all water filters have the same power of filtration and cannot remove all contaminants, while the capacity of how much water can be filtered at once is also an issue, as is longevity and how much replacement filters will cost and how much waste they will generate.

What contaminants can be found in drinking water?

The contaminants that can be a problem in water include:

  • Microparticles of plastic
  • Bacteria for example salmonella, E. coli and cholera
  • Waterborne cysts such as cryptosporidium and giardia, which cause stomach illnesses
  • Disinfectants, including chlorine
  • Rust and foreign particles
  • Heavy metals,including lead

As different approaches are needed to remove these a multi-layer water filter, such as an Undercounter Water Filter will provide a more comprehensive solution.

When choosing a water filter it is important to know what contaminants you want to make sure are not in your water and whether your chosen water filter is effective at removing them.

How filter jugs work

Filter jugs are a commonly used device to filter water but they do have limitations. While being flexible and easy to use this does come at the compromise of capacity and long-term performance.

Many filter jugs focus solely on the removal of chlorine to improve the taste of drinking water by using activated carbon to remove chlorine. The nature of activated carbon makes it unsuitable for removing most other contaminants.

Prone to limescale build-up, the effectiveness of these filters can be reduced by limescale deposits and the filter will usually need to be replaced frequently. Some jug filters also incorporate ion exchange resins to target limescale as well as heavy metals.

A problem with filter jugs is capacity and longevity. There is a limited amount of water that the jug can hold and it is necessary to wait for the water to move through the filter before using it. If you were using it for cooking or serving several people you would need to think ahead and store the water.

Due to limescale build-up the effectiveness of many jug filters can also be quickly reduced, they will often need to be replaced after two months.

How under-counter filters work

Undercounter water filters are well regarded for their efficiency, powerful filtration and for providing water on tap.

Most undercounter water filters will combine a number of methods to achieve excellent levels of filtration. Doulton Water Filters uses ceramic technology at the heart of its filters to remove up to 99.99% of common contaminants, which has been verified in tests.

The make-up of the porous ceramic membrane is such that it can filter particles out down to a size of just one micron. The micropores in this ceramic outer shell work to stop bacteria, plastic micro-particles and waterborne cysts getting into your drinking water.

Activated carbon is also used to target disinfectants, such as chlorine as well as organic chemical compounds to improve the taste and colour of the water.

Reduction media is incorporated to reduce heavy metals and, finally, scale inhibitors are added to prevent limescale build up.

All this technology is packed neatly into filter candles that fit discreetly under the sink to directly serve the cold water supply and provide fresh, clean water on tap with no need to plan ahead for how much is needed.

The structure of the ceramic water filters also allows them to work at full capacity for between six to 12 months, cutting down on waste.

Doulton water filter candles are available in different specification to suit your own needs regarding water filtration. When choosing a water filter make sure that you choose a filter that does what you want it to. Find out more about the water filters available from Doulton here.


Daniel Berko