Nano Filter features very fast filtration, an accuracy of 0.002 μm, a patented Swiss technology and a single cartridge that is supposed to filter 4,000 liters. In the APS promotional email on the date of Friday, May 15, 2026, Nano is presented as a "HUGE revolution", "50 times more precise" than Coldstream, with a flow rate of 18 litres per hour, or "the equivalent of a large glass of water per minute".

It's a very strong commercial argument. It's visual, simple, easy to understand.

But in water purification, speed is not enough. The real issue is not which filter fills a glass the fastest. The real issue is to know what remains in the water at the finish.

There's no point in running, but you have to arrive with really controlled water.

When marketing runs faster than evidence

In the market for gravity water filters, there are two opposing approaches.

• The first is to publish complete tests, name the laboratories, indicate the standards used, specify the contaminants tested, the volumes filtered, the detection limits and the exact conditions of the tests.

• The second is to talk about "revolution", "Swiss nanofiltration", "0.002 μm", "50 times more accurate", "bacteria and viruses destroyed", "TFA eliminated", then to show water flowing very quickly.

Nano Filter clearly plays this second card.

The brand claims two patented technologies, PlasmaShield-NanoMatrix and Nanoporous Adsorber Fleece, which are supposed to allow a level of filtration inaccessible to conventional gravity filters. On its technology page, Nano claims that its membrane destroys pathogens and that its system reaches 0.002 μm, "50 times more accurate" than conventional gravity filters.

Note: these names do not seem to be unique to Nano Filter. Swissreg lists PLASMASHIELD-NANOMATRIX and NANOPOROUS ADSORBER as associated brands with Evodrop AG, a Swiss company active in water treatment. This suggests that Nano is likely based on a technology, license, or vocabulary from this Swiss ecosystem. This is not, in itself, proof of ineffectiveness. But it's also not proof of performance under real-world gravity conditions: a trademark, proprietary technology, or data sheet is no substitute for a full lab report on the final product.

The same page goes so far as to write: "PFAS, pesticides, drug residues, heavy metals: nothing gets through."

This is a massive promise.

But a massive promise requires massive evidence.

➜ And this is precisely where the Nano file becomes fragile.

To remember

The flow rate is a criterion of comfort. Not a proof of purification.

A filter can fill a glass very quickly while leaving the essential questions open:

• Which contaminants were actually tested?
• By what method?
• On how many liters?
• With what detection limit? 
• And with which comprehensive reports are available ?

Nano showcases spectacular speed. But in the end, when you compare the available public evidence, Coldstream FTO+ remains much more solidly documented: tests according to recognized standards, identified laboratory, wide range of contaminants, results at 3,000 L, and even a clearly named virus test.

Speed does not purify water

Nano's central argument is simple: it goes fast.

In the APS email dated 15/05/26, The flow rate is presented as "unparalleled", at 18 liters per hour. The message insists on the visual comparison with a transparent tank, as if the speed was enough to demonstrate the superiority of the filter.

On its product page, Nano advertises a cartridge at 0.3 L/min, a lifespan of 4,000 L or 12 months, and "15x faster" filtration. The same page also highlights "1 glass of filtered water per minute".

Very well. It's fast.

But a fast flow does not prove better purification.

The flow rate answers a practical question: how long should you wait?

The tests answer a health question: what am I really drinking ?

To confuse the two is to take a stopwatch for a laboratory report. Water can pass through a cartridge quickly without it showing anything about TFA, viruses, pesticides, nanoplastics, heavy metals or drug residues.

In filtration, speed is an advantage of use. But safety is proven by tests, not by a speed video.

  

The 0.002μM: A spectacular figure but not universal proof

Nano claims to achieve a filtration of 2 nanometers, or 0.002 μm, and presents this as "50 times more accurate" than a conventional gravity filter. The brand even writes that "PFAS, pesticides, drug residues, heavy metals: nothing goes through".

It's a very strong sentence. Too strong.

Dissolved chemical contaminants do not filter like sand through a sieve. PFAS, drugs, pesticides or heavy metals are not simply "particles" that are blocked because they are larger than a pore. Nano indirectly acknowledges this by explaining that PFAS are captured by hydrophobic interaction, pesticides by molecular affinity and heavy metals by electrostatic attraction or complexation.

So if Nano wants to prove effectiveness on these contaminants, the "0.002 μm" is not enough.

Contaminant-by-contaminant testing is required, with specific conditions, inlet concentrations, detection limits, flow rate, filtered volume, replicates, and complete reporting.

Otherwise, "0.002 μm" becomes mostly a slogan. A nice slogan, certainly. But a slogan nonetheless.

TFA: a claimed figure, not verifiable proof over time 

Nano claims a result on TFA, trifluoroacetic acid: 0.738 μg/L before filtration, "n.d." After filtration, reduction displayed at 100%. This result is associated with Bureau Veritas Report 424-1242/A.

On paper, it's impressive.

But we have to look at what it really proves.

• First, "n.d." does not mean "zero". This means "not detected below the instrument's detection limit". However, without the full Bureau Veritas report, the consumer cannot verify the exact detection limit, the method used, the water matrix, the pH, the TDS, the flow rate, the repeats, the number of cartridges tested or the volume actually filtered before the test.

• Secondly, Nano itself specifies that an "additional test" on performance at 5,000 liters is still underway and will be published after receiving the results.

So even if we accept the Nano synthesis as is, the TFA is not publicly proven at 4,000 or 5,000 liters.

It is claimed in a painting. It's not the same thing.

And this is a major point, because TFA is precisely one of the most difficult PFAS to remove. The TZW states that TFA cannot be removed by natural or conventional technical treatments of drinking water, and that ozonation, activated carbon or chlorination are practically ineffective; the TZW also indicates that the reduction of TFA in drinking water treatment is only really possible by reverse osmosis, with strong reservations about its generalization. The German agency BfR/UBA also describes TFA as highly persistent and highly mobile, with low affinity for sediment and activated carbon filters.

Conclusion 

Nano claims a result on the TFA. But without a full Bureau Veritas report, a clearly published detection limit and an end-of-life TFA test, this claim is not enough to prove sustainable performance over 4,000 liters.

A TFA promise without a full report is like a racing car without a technical inspection: it can shine, but you don't know if it holds up.

Virus: one claim but no visible virus test

Nano explicitly talks about viruses.

On its technology page, the brand claims that upon contact with the membrane, "a bacterium, virus or any other pathogen" would have its envelope pulverized and its DNA broken. On the product page, Nano also claims that the cartridge "destroys bacteria and viruses on contact with it".

The APS email, dated 15/05/26, repeats this promise by stating that Nano filters "bacteria, viruses and pathogens", and that "all filtration performance has been validated by independent laboratories, accredited ISO 17025".

The problem? In the Nano public register, we do not see any specific virus tests 

The organisms listed are: Total coliforms, E. coli, P. aeruginosa and S. aureus. They are bacteria. Results are expressed in bacterial units, not viral units. We don't see coliphagous MS2, no rotavirus, no surrogate norovirus, no PFU unit, no identifiable viral protocol.

It's a very serious shift in vocabulary.

Testing bacteria does not prove effectiveness on viruses. They are not the same organizations, not the same sizes, not the same structures, not the same validation protocols.

So yes, it's suspicious. And technically, it's not serious.

When a brand talks about viruses in its commercial promise, it must display a virus test. Not a bacterial table with the word "virus" in the title.

 

By way of comparison, Coldstream FTO+ explicitly displays a "Virus" line with Rotavirus spp., an input concentration of 2.4642 × 10⁷ PFU/L and a reduction >99.99% at 3,000 litres.

There, at least, the viral contaminant is named. The protocol is identifiable. The unit is coherent. We don't ask the customer to guess.

Nano is about viruses. Coldstream shows a virus test.

It's not a detail. This is a major difference.

 

Microplastics and nanoparticles: another slip 

Nano claims to be effective on microplastics and also mentions nanoplastics. APS email even goes so far as to talk about "microplastics, including nanoparticles".

But in the Nano public tests, the published results are on particles >5 μm and >10 μm. And Nano itself specifies that an additional test on nanoplastics smaller than 1 μm is underway.

So here again, we must distinguish between promise and proof.

Saying "we tested for particles >5 μm" is one thing.

To suggest that nanoparticles or nanoplastics are demonstrated in the laboratory is another.

As long as the nanoplastics test <1 µm n’est pas publié, cette promesse reste non démontrée publiquement.

 

Full reports: a summary sheet is not a certification 

Nano displays results and cites references: SGS Report NBF24-0013449-01, SGS Report NBF25-0023352-02 and Bureau Veritas Report 424-1242/A. The brand also claims that the tests are carried out by SGS and Bureau Veritas, two independent ISO/IEC 17025 accredited laboratories.
As of the date of this analysis (15/05/26), we have not found a link on Nano's public pages to download the full SGS and Bureau Veritas reports. Only report references and summary tables are visible. If these full reports are published at a later date, the analysis will naturally need to be updated.

But on the public pages viewed, the consumer does not see the complete original reports with all the pages, the laboratory header, the exact address of the test site, the scope of accreditation, the detailed methods, the contaminant-by-contaminant detection limits, the water conditions, the repetitions and any disclaimers.

And this is precisely what you should look at before buying a filter. Our guide recalls that a reliable filter must indicate:

• Who makes the product
• Which lab tested
• If the laboratory is ISO/IEC 17025 accredited
• What standards were followed
• If the product has an official certification

He also points out that a simple "SGS test" without details is not a sufficient guarantee.

Another point to be clarified : Nano cites SGS references of type NBF. However, SGS public reports with the same type of NBF prefix are issued by SGS-CSTC Standards Technical Services Co., Ltd. Ningbo Branch, China. This does not prove that the Nano NBF24-0013449-01 report is identical or issued under the same conditions, but it does make it essential to publish the full report to know the exact SGS site, the scope of accreditation and any limitations of use.

Coldstream, on the other hand, has a more classic, less sexy, but much more readable file: tests according to NSF/ANSI 42, 53 and P231, by IAPMO R&T Laboratory in New Jersey, with ISO 17025/NELAC compliance. The Coldstream Fact Sheet also indicates a 1,500 L rated capacity, a recommendation for replacement every six months, and results up to 3,000 L on several contaminant families.

Nano has a summary sheet.

Coldstream has a much stronger normative record.

 

The test panel: Nano tests little, Coldstream documents extensively

Nano displays results on several families of contaminants. But when you look at the details, the panel is very targeted.

• For pesticides, Nano publishes two main molecules: dimethoate and carbofuran.

• For drugs, Nano publishes two antibiotics: roxithromycin and oxytetracycline.

• For heavy metals, Nano highlights three metals: lead, mercury and cadmium.

That's no small thing. But it's not a wide range.

Coldstream FTO+, documents many more families and many more molecules: heavy metals, volatile organic compounds, semi-volatile organic compounds, pesticides, herbicides, pharmaceuticals, particulate matter and HAA5. In particular, the sheet shows many pesticides and herbicides at 3,000 L, with many reductions of more than 99%. It also displays a wide range of pharmaceuticals and endocrine disruptors at 3,000 L, as well as HAA5 results.

The difference is simple:

Nano selects a few contaminants that sell very well.

Coldstream documents a much broader behavior. Nano speaks broadly.

Coldstream documents widely. It's not the same.

The lifespan: 4000 liters announced, but not all the promises are proven at 4000 liters

Nano announces a cartridge for 4,000 liters or 12 months. The product page even claims constant effectiveness for 4,000 liters, "without progressive degradation".

But we have to look at it family by family.

On certain contaminants, Nano shows results after 5,000 liters: heavy metals, pesticides, drugs, chlorine, bacteria, particles >5 μm and >10 μm.

But on short PFAS and TFA, Nano says that the additional test at 5,000 liters is still ongoing.

On nanoplastics <1 µm, Nano indique aussi que le test complémentaire est en cours.

On viruses, no specific virus test is visible in the public register.

So we can't seriously write that all the great Nano promises are proven on 4,000 liters.

We can write that some families are tested at 5,000 liters.

But TFA, nanoplastics and viruses remain major weak points.

Coldstream takes a different approach: the sheet shows a rated capacity of 1,500 L and recommends replacement at least every six months, while publishing results up to 3,000 L. On certain parameters such as fluoride, nitrate or chlorine, the sheet clearly shows that performance decreases with volume: this is not always flattering, but it is precisely what makes the file more credible.

Coldstream does not claim to do everything for 4,000 liters.

He shows what he's doing, and also where it's falling.

It's less salesy. It's more serious.

 

"Swiss technology": okay, but where is the cartridge made? 

Nano strongly promotes "patented Swiss technology" and Swiss development. At this stage, we have not identified any public patent clearly attached to the Nano Filter product.

Based on the original product elements we have, the Nano cartridges are most likely made in China.

The problem is not that a product is made in China. Very good products can be made in China.

The problem is the discrepancy between a very "Swiss" oriented communication and the lack of clear public transparency about the actual manufacturer, the country of manufacture of the cartridge, the factory, the OEM and the complete reports.

When a brand puts so much emphasis on the Swiss flag, the consumer must be able to know what exactly is Swiss: society? The patent? The design? the cartridge? The membrane? The factory? assembly ?

Without this precision, "Swiss technology" becomes a marketing cover rather than traceability information.

Conversely, the Coldstream plug clearly states that the CF163W filter is manufactured by KLT Filtration Ltd in King's Lynn, UK, and mentions "Made in the United Kingdom". Again, it's not a question of the flag. It is a question of transparency.

Targeting the installed base: Nano doesn't just sell a filter, it wants to replace existing cartridges

The APS email, dated May 15, 2026, does not just recommend a complete new system.

It is also intended for people who are already equipped with a gravity tank. The message tells them to keep their tank, then "upgrade to the next technology" by replacing their existing cartridges with Nano's. He also claims that the cartridge is compatible with tanks of all brands on the market.

The Nano product page explicitly lists several compatible systems, including Pure Filters, Berkey, British Berkefeld, ProOne, Purewell, Phoenix and Weeplow.

So it's not just a new competitor.

It is a strategy for capturing the installed base.

And when a brand says that all you have to do is change the cartridge to move to a "superior technology", it has to provide superior proof.

Not just better throughput.

 

Summary Comparison Table 

Criterion	Nano Filter	Coldstream FTO+
Main argument	Velocity, 0.002 μm, Swiss technology, 4,000 L	Documented tests, standards, identified laboratory
Flow rate	Very fast: 0.3 L/min	Slower
Flow rate = health proof ?	No	No, but Coldstream does not base its proof on speed
Reports	SGS/Bureau Veritas references displayed, but full original reports not publicly visible on the pages viewed	Detailed sheet with standards, laboratory, contaminants, volumes
Standards	Announced ISO/IEC 17025 Tests	NSF/ANSI 42, 53, P231, IAPMO, ISO 17025/NELAC
TFA	Claimed result, but 5,000 L test still in progress	Doesn't claim what isn't documented
Viruses	Commercial claim, but no specific virus test visible on the public register	Rotavirus spp. tested at 3,000 L, reduction >99.99%
Nanoplastics	Promise mentioned, but test <1 µm en cours	More framed claim on particles/microplastics
Pesticides	2 main molecules displayed	Wide range of pesticides/herbicides at 3,000 L
Medications	2 antibiotics displayed	Wide pharmaceutical panel at 3,000 L
Origin	Swiss communication, cartridge made in China according to our product elements	Clearly identified UK manufacturer
Transparency	Strong promise, partial evidence	More complete and verifiable record

 

Simple questions to ask before buying

Before purchasing Nano Filter, one should ask:

• Where exactly is the cartridge manufactured ?

• What is the name of the manufacturer or factory ?

• Are the full SMS reports NBF24-0013449-01 and NBF25-0023352-02 available ?

• Is the full Bureau Veritas 424-1242/A report available ?

• What is the exact limit of detection for TFA ?

• Is the TFA/PFAS test after 4,000 or 5,000 liters published ?

• Is there a complete virus test with MS2, rotavirus or other viral indicator ?

• Is there a nanoplastics test <1 µm publié ?

• Does the product have NSF, IAPMO, or WQA certification, or just spot testing ?

A transparent brand must be able to answer these questions simply

Conclusion: Nano goes fast. Coldstream arrives with its proofs. 

Nano Filter has a very good storytelling.

The brand talks about nanofiltration, Swiss technology, 0.002 μm, 18 L/h, TFA, viruses, nanoplastics and 4,000 liters.

But when we compare the publicly available evidence, several major promises are not demonstrated at the level at which they are claimed.

⮕ The TFA is displayed as "not detected", but the full Bureau Veritas report is not publicly visible and the 5,000-liter PFAS test is announced as still in progress.

⮕ The viruses are claimed, but the public board shows bacteria, not an identifiable virus test. No MS2. No rotavirus. No norovirus surrovirus. No FPU unit. For a microbiological promise, this is a real problem.

⮕ Nanoplastics are being talked about, but Nano says that testing <1 µm sont encore en cours.

Pesticides and drugs are tested on a few molecules, while Coldstream publishes a much wider panel.

⮕ And on traceability, Nano highlights Switzerland, while the actual manufacture of the cartridge must be clearly assumed and documented.

The fastest filter is not necessarily the safest.

In water purification, it's not the speed that counts at the end: it's the contaminants actually tested, the methods used, the volume filtered before testing, the detection limits, and the transparency of the reports.

Based on the available public evidence, Coldstream FTO+ remains today the most solidly documented filter of this comparison.