The Truth About Water Filters

Water filtration is crucial to ensure clean and safe drinking water.

Coldstream and Doulton/ British Berkefeld are two popular brands offering filtration solutions, but their certifications and testing methods differ.

This article examines these differences, specifically NSF certification, and sheds light on some marketing practices. Recently, the French company responsible for marketing Doulton British Berkefeld in French-speaking Europe published misleading information. We want to bring some clarity and objectivity.

Coldstream Filters

Coldstream filters, including the FTO+ model, are known for their ability to remove a wide range of contaminants, such as fluorine, nitrates, viruses, bacteria, chemicals and heavy metals.

While these filters may not always have full NSF certification, they are independently tested to NSF standards, ensuring their effectiveness.

Doulton Filters

Doulton British Berkefled, with its Ultra Sterasyl filters, offers NSF certified products. However, these filters use older ceramic technology and have not been tested for virus removal.

Their efficiency in filtering bacteria is log >99.99%, slightly lower than that of Coldstream filters (log 99.9999%).

Proof that the NSF standard is not the ultimate proof that a filter works, which the French company that markets Doulton knows very well since it has claimed for years to have the NSF standard on this filter, a standard that Doulton obtained at the end of 2023. Doulton's ultra fluorides do not have the NSF standard, yet that does not prevent them from selling them.

Write to us on info@pure-filters.com to obtain the complete file.

The Myth of NSF Certification

NSF certification is often perceived as the ultimate benchmark of quality. However, it is important to understand that this certification, while useful, is not the only indicator of a filter's performance.

Independent testing to NSF standards is often more rigorous and comprehensive than that performed for official certification. These independent laboratories can test additional parameters and subject the filters to more stringent conditions, providing additional assurance of their performance.

Technology comparison: beyond labels

The comparison between Doulton British Berkefeld's Ultra Fluoride filters and Coldstream's FTO+ reveals a diversity of technological approaches. However, the comparison with Doulton's Ultra Sterasyl filters is inadequate, as they are not designed to remove fluorine.

However, Doulton Berkefeld's Ultra Fluoride filters do not have the NSF standard (in the year 2024) and do not remove chemical contaminants either.

Coldstream's FTO+ filters demonstrate a unique ability to filter a wide range of contaminants, including viruses, bacteria, chemical contaminants, fluorine, nitrates, heavy metals, putting these filters in a league of their own.

Comparison under the magnifying glass

Coldstream ceramic : based on diatomaceous earth, it is assembled using an innovative technique under high pressure. Elimination of bacteria (log 99.9999%), parasites and viruses (tested on rotaviruses 99.99%)

Doulton Berkefled ceramic : Much thinner in thickness, it is assembled using an old and outdated method. Elimination of bacteria (log 99.99%) and parasites, does not filter viruses.

Coldstream Activated Carbon : new, modern formula allows this activated carbon to have a strong protective effect on nitrates and to eliminate fluorine (in addition to other contaminants.

Doulton Berkefeld Activated Carbon : An old and outdated formula, has no effect on nitrates and fluorine and offers removal on chemical contaminants and heavy metals.

Learn more about Coldstream technology and understand why these gravity purifiers are the best performers on the market.

In conclusion

Relying solely on NSF certification can be misleading.

While this certification provides a guarantee of quality, independent testing to equivalent standards can be just as, if not more, reliable. Coldstream filters, while not always NSF certified, have demonstrated their effectiveness through rigorous independent testing, sometimes exceeding the requirements of official NSF certification.

For an informed choice, it is crucial to consider the results of independent tests and understand that NSF certification, while important, should not be the only criterion.

Coldstream and Doulton filters each have their advantages, but the key is to choose a product that best meets your specific water purification needs.

We will make the same comparison about the pressure systems of Doulton VS Coldstream. If you look at our spec sheets and compare with Doulton, you'll quickly guess that the conclusion will be identical to this article.