General FAQs

Water is perhaps the most simple molecule with compound complexities that is crucial for the existence of life.  An eminent UK Science journal, the New Scientist, says “WATER is essential for life as we know it, but why?  A new analysis may rewrite the idea that it is solely the medium in which the reactions that drive life occur, instead of viewing it as an active participant.”  (20 January 2021 article)

It stands to reason that since water is so central to life, purer is better.  Indeed, many articles allude to the fact that drinking a sufficient amount of pure water leads to better health:  it helps keep body weight down, fights fatigue, promote better skin complexion, the immune system, prevents kidney stones and brings about many other health benefits.

All of these simply underline the fact that because the body is made up of mostly water, drinking a sufficient quantity of pure water is critical to health.

However, water nowadays is often tainted by impurities.  The Flint water crisis in the USA shows that even 1st world countries can have severe water purity problems in their water supply – in that case it was lead and bacteria.

There are naturally occurring impurities in many parts of the world – such as arsenic and fluoride.  These are toxic to human life.  There are also microorganisms and viruses that occur naturally which may be potentially harmful; hence the use of disinfection in water supplies by water authorities and municipalities.  While disinfection is an important and crucial step to provide safe drinking water, the disinfection process of chlorination or chloramination creates disinfection by-products.

Disinfection by-products are created when humic acids, which are formed when dead organic material sits in water reservoirs, react with the disinfection chemicals.  By-products are formed in trace quantities, of which trihalomethanes (THMs) are the most obvious.  Spectral analysis shows that there are hundreds of such compounds, some of which are in such minute quantities that their molecular structures cannot be determined: https://www.ncbi.nlm.nih.gov/books/NBK234591/.  Those who keep fish often find that chloraminated water can kill their pets.

There are also industrial contaminants that somehow find its way into the drinking water system. Minute amounts of paints, herbicides and pesticides and common industrial cleaners, can find their way into the drinking water system.

The answer to this will be region specific.  For many countries the answer would be yes, because the municipalities in these countries have to supply water at an affordable rate for every purpose – washing clothes, flushing the toilet, bathing and so on.  In some countries, water is simply filtered by sand filters and sent into the water distribution system, with or without proper disinfection. 

Singapore is among many countries which has very good municipal water.  It has water parameters that are beyond those stipulated by the World Health Organisation.  Singapore’s water more than meets ‘safe’ levels.

However, if we consider drinking water, it is apparent that there is a taste difference between tap water and bottled water.  Many consumers still prefer to buy bottled water.

From an environmental viewpoint, it is greener to have a refillable water bottle and re-fill this, instead of discarding a single use plastic water bottle. 

From a financial viewpoint, the cost to re-fill a water bottle with purer home-filtered water is much less than the cost of industrial bottled water.  

Another benefit of a reliable water filter, is that it can reduce trace disinfection by-products.

In these days where fakes abound, it is important to have a vendor who ensures that the supply chain cannot be compromised and that products are genuine.  Water filtration directly impacts what we put into the body.  It is important that the water filters perform to proven integrity standards.   Besides cost, one should consider water filters that can significantly reduce common contaminants. 

  • The Filter should contain anti-bacterial elements – this is basic
    Different parts of the filter system should not breed mould or fungus over time.  Filter elements that contain silver similar to Coldstream® ceramic filters or other anti-bacterial media, offer the assurance that there is no colonization of harmful bacteria within the filter itself.  Without this, an inferior filtration system can pollute your water instead.

Many filtration systems that are trending offer multiple cartridge systems that may lack individual anti-bacterial elements.  Carbon-containing media can become a playground for bacteria.  Multiple stages can each become nasty bacterial breeding grounds.

  • Make sure the product has accreditation, even if partial
    Many water filters perform well for the first few hundred litres of water, but rapidly degrade in performance after, or when, it is subject to tougher conditions.  Many low quality filters can appear to perform well at low water pressures and in low contaminant challenges.

    Check for guarantees of quality standards passed. The quality of your drinking water filter is very important.  It is vital to ensure specific standards are not misrepresented with purported health benefits.
  • Make common-sense selections
    This may seem obvious, but the fact is that many ultra-low-cost systems are not effective filters at all.  Check that the housing is made of food-grade material of decent quality, and check that the filter actually does – well – something.  Technological design and brand is a bonus, but crucial to every system is good filtration integrity and continuous filtration performance of the drinking water purifier.

    If you are buying from another reputable brand, make sure you are not given an imitation product.  Counterfeits of relatively famous brands have been released out in the market.  These counterfeit products carry identical claims.  Ceramic counterfeits are possibly dangerous because filtration integrity is severely compromised, e.g. when the silver content leeches out, or the pore size is too large to be effective, or the ceramic quality is poor and cracks as time passes, among other problems.

We bid you well in your momentous decision to buy a water filter.
Or you could just pick up our Coldstream® water filters worry-free here.

Arkwater® supplies drinking water filters that can remove a wide range of trace contaminants, in many cases by over 99%, to create a drinking water that is mostly scrubbed of contaminants. 

Arkwater® ships directly from the UK manufacturer.

Ah, now we are getting to the real stuff. The question is being asked and answered by millennials everywhere.  We will proceed with caution, our short answer being:

We are not certain, but we don’t think so.

The body has a mechanism called the homeostasis in which variables are regulated so that internal conditions remain stable and relatively constant.  Examples of homeostasis include the regulation of body temperature, and the balance between acidity and alkalinity. Even in a snowstorm or in the desert, the body will regulate its temperature to as close as possible to around 36.5oC.  The body fails to do this when it cannot due to illness or extreme exposure.

Similarly, the body regulates acidity and alkalinity and does not allow the level to change in the blood.  If the body did not do this, the pH level in the blood would change which would lead to severe shock.  Hence the only place which alkaline water could effect would be in the gut.

But we know that yoghurt, which is probiotic, is acidic, with a pH of around 4-5. And even though yoghurt is acidic, it acts against acid reflux, which is counterintuitive.

There are a host of companies globally claiming to offer the purported benefits of alkaline water in visually stimulating packages, such as trendy water bottles or fancy electric ionizers.  However, there is a distinct lack of long-term medical research that supports or verifies positive causality.

In the USA, the FDA has urged people to avoid Real Water-branded alkaline water after five Nevada children who drank it were hospitalized with liver failure. There have also been some class action lawsuits in the USA over “Truth in Advertising”, the main being that alkaline water has falsely been marketed to have health benefits.

One argument against alkaline water is that our own body’s function of acid-base homeostasis opposes this, as it is responsible for maintaining the pH of extracellular fluid (even before ingested materials hit the bloodstream).

Another argument is that every human’s stomach pH is ranges from 1.5 to 3.5, effectively neutralizing immediately whatever extra few ions you throw into it.  A quick search into actual scientific articles bring up the words ‘quackery’ and ‘pseudoscience’.

Conversely, there are so many products and reviews, that it is hard to refute that there could be intangible and real long-term benefits.

If you are still reading, well done – you’ve just entered the big-boy league of water FAQs.

Heterotrophic bacteria refers to organisms that do not photosynthesize – which is over 95% of all bacteria, inclusive of both beneficial and harmful bacteria.  Bacteria are living organisms and they naturally exist everywhere because they are part of the environment.

Some are good bacteria. For example, the probiotics and prebiotics, as discovered by Nobel prize winner Eli Metchnikoff.  These include bacteria found in yogurt, cheese, yeast, and in our human stomachs, which are part of the normal gut microflora such as Lactobacilli and Bifidobacteria.  In recent years, it is becoming increasingly common for people to consume these heterotrophic bacteria as dietary supplements to health.

Other heterotrophic bacteria are pathogenic (disease-causing).  In our water context, the presence of these pathogenic bacteria is measured by the amount of Escherichia Coli (commonly known as E. Coli) which are found in the lower intestines.  Since E. Coli can only survive for a short while outside the body, their absence makes them a good indicator organism for faecal contamination.  The specific measurement of E. Coli in water, (as opposed to simply ALL heterotrophic bacteria), has become the prescribed way to measure the safety of drinking water.

Wow, you are still here. Go ahead and give yourself a pat on the back.

HPC is a method used to measure the amount of heterotrophic bacteria in water. One millilitre of water is cultured on an agar plate, and the number of formed colonies is counted. This reading does not indicate the presence of pathogenic organisms; hence HPC is not used as a standard for measuring water quality. The US Environmental Protection Agency set a water benchmark of 500 cfu ml-1 (colony-forming units per millilitre), as high concentrations of HPC bacteria can interfere with coliform analysis.

According to Health Canada, “Rudimentary testing for heterotrophic organisms became possible with the advent of culture media in the late 1800s. By the end of the century, HPC tests were being used as indirect indicators of water safety by providing information on the treatment process – that is, they indicated the level of removal of bacteria by filtration.”  Health Canada continues, “The use of HPC as a safety indicator decreased in the 20th century with the advent of faecal-specific testing.”      

One way to understand this to consider a simple human analogy.  Within a human population there will be the large majority of good people and there may be some bad people.  HPC is akin to measuring the presence of people in an area and concluding that since there are people, there is a proportional amount of bad people within them.  Obviously, this was not a good or even particularly scientific method.

A better way to measure bad people would be to look at the crime statistics – and that’s sort of like what the E. Coli tests are about.  This is why HPC has ceased to be used as an indicator for water safety, just as a population census is not used to find criminals.  Similarly, one can explain the EPA’s reason for the establishment of their HPC level through another analogy. The larger the population, the harder it will be to find the negative portion within that body with certainty.

According to the World Health organisation, a study was conducted among families in Connecticut, USA (Calderon 1988) who were randomly assigned either a blank filter or a granulated activated carbon (GAC) filter. The study covered over a total of 600 person years. There was regular monitoring of water quality and human health. Water from taps fitted with GAC filters had substantially higher heterotroph counts (mean >1000 cfu/ml) compared with unfiltered water (mean 92 cfu/ml). However, at the end of the study, there was no statistical health difference between people receiving water with high HPC and low HPC.

A further study was conducted in 1991 and came to the same conclusion (Calderon and Mood,1991). A further trial was conducted in 1997 (Payment, 1997) with several groups of people; one group drank chlorinated tap water, some were given bottled effluent water, and lastly some were given effluent water further treated by reverse osmosis (RO). In the 2 groups using bottled plant effluent water, there was significantly higher HPC detected. Despite this, the gastrointestinal illness rates were not significantly different between the high HPC and low HPC groups – in fact, the illness rate in the group with lower HPC was actually higher.

A quick summary: The World Health Organisation has concluded that studies demonstrate there is no association between total counts of HPC bacteria and illness in humans.