Arkwater.com. Because Water is Life.
is the history of Doulton® and British Berkefeld® Water Filters?
Do I need a water filter?
It may seem not, if you are in a country
with very reliable source of municipal water.
Some people think that chlorine is good for the body. Is it?
No, a small amount of floride (not chlorine) is added to strengthen the teeth. But chlorine is a low strength poison which is used to kill bacteria. Chlorine does not have any health benefits.
Some studies show that chlorine reacts with humic acids and other natural organic compounds present in water, which can lead to the formation of trihalomethanes (THM), a group of carcinogenic chemicals.
Doulton® SuperSterasyl & Ultracarb water purifiers reduce both the chlorine and trihalomethanes from drinking water. Doulton®'s filters produce clean, safe, drinking water that is purer, tastes better, and brings out the flavour of home-brewed drinks.
What is the impact of purer drinking water?
Water is vital for good health - our lives
depend on it.
There is no magic to purer drinking water.
Drinking purer water can lead to better health.
Water pollutants are increasing worldwide.
An alarming component is the cancer-causing group of trihalomethanes.
Lack of clean water causes many diseases. Natural contaminants
in unfiltered water may cause a sensitive body to hit the
tolerance level for histamines, and increase the prospensity
to allergic reactions when exposed to other chemicals.
What should I look out for when choosing a drinking water purifier?
The fact is that technological design and quality manufacturing of both the filter element as well as the housing, are critical to the lifespan, the filtration integrity and the continuous performance of the drinking water purifier.
Is a 6-element system better than a 1-element system?
Some other 2-6 filter media systems add
alkalinity to drinking water. Is this a good thing?
Alkaline water at high pH levels may be suitable for some patients with certain medical conditions. However, a healthy person should think carefully before drinking water to which more alkalinity has been artificially added.
How can the Doulton®'s 1-element filter perform so many functions?
Can the Doulton® filters remove chloramines?
Chloramines (instead of chlorine) are being increasingly used in municipal water treatment plants for sterilization of water. Potable water with residual chloramine is considered to be a problem or potential problem to many industries, particularly those related to rearing or keeping of pond fish, hatchery fish and aquarium fish.
Catalytic activated carbon (made from bituminous coal) is able to effectively remove chloramines. Reverse Osmosis membranes are generally unable to do so.
Activated carbon with small pores (versus large pores) and a large surface area, is also generally able to effectively reduce chloramines, provided the flow rate of water allows sufficient contact time.
Doulton®'s Ultracarb Filters have been manufactured with small-pored solid carbon blocks to reduce trihalomethanes, and these small-pore-sized carbon blocks are consistent with those used to remove chloramines.
Doulton® technical manuals indicate
that Doulton®'s carbon filters (like the Supercarb and the
Ultracarb) will reduce the amount of chloramine in the water
but it will not remove it totally depending on the flow rate
of water (A figure of 1 gallon per minute, or about 3.7 litres
per minute, is often quoted as the maximum flow rate after which
chloramines removal becomes ineffective because the contact
time is insufficient. The average flow rate through the
Doulton® Countertop with Ultracarb, is typically around
2 litres per minute, based on the normal water pressure provided
in municipal piping to residential households. One
can manually set the flow rate to be even slower just by turning
For pressure-filters, manually adjust your source tap to run the water through the Doulton® SuperSterasyl or Ultracarb filters, to the slowest-possible constant flow. This maximises contact time with the in-built Doulton® carbon elements to yield great-tasting water.
Doulton® however does not currently
publish test data to show how much chloramines are removed as
there is not yet a widely accepted global standard for chloramine
Is it expensive to maintain a Doulton® Water Purifier?
Not at all.
While Distillation systems and Reverse Osmosis systems generally incur significant electrical power consumption, Arkwater.com's Doulton® water purifiers do not need electricity at all.
The Ultracarb filter in the Countertop and Undersink models
have a guaranteed performance of 2,244 litres. The high
product reliability allows the Doulton® filter to perform
way beyond these guaranteed levels. Existing
arkwater.com customers in Singapore, with 3-5 members in their
households, have used the Doulton® ceramic filters for easily
over 15 months.
When do I clean the Doulton® ceramic filter element?
When the time it takes for the water to filter through
decreases to the point where it is no longer meeting your daily water
How do I clean the filter element?
Hold the Doulton® ceramic element under clean running water while scrubbing
lightly with a green scouring pad like 3M ScotchBrite pad or soft-bristled
How do I determine when the granular carbon in the ceramic element is exhausted?
When bad taste and odor of the source water is no longer removed. The good news is that the Doulton® ceramic shell will continue to remove pathogenic harmful bacteria even after the carbon is exhausted. If your water tastes bad, you may continue to use your Berkefeld® to remove harmful bacteria, and either pre-filter or post-filter the water with an inexpensive carbon filter, such as a Brita.
How do I know when to change the filter element?
Doulton® filters are completely reliable,
and will continue to remove harmful bacteria and water-borne
cysts until the very
end. The water-flow will simply slow down because of accumulated
filtered contaminants, and when a repeated cleaning does not
increase the water-flow, it is time to change the filter. Alternatively,
the ceramic element will become slightly smaller from repeated cleanings. Eventually, the ceramic wall will wear
thin and crack. Once a crack
occurs, the integrity of the filter has been lost and it must be replaced.
Is it possible to reactivate or regenerate the granular carbon in the filter element once it becomes saturated with chemicals?
In an emergency situation while out in the field,
yes. To some extent, some chemicals such as chlorine can be removed from the carbon by
boiling the ceramic filter element in water for five minutes.
Can I prolong the need for cleaning the filter elements?
Yes. You can pre-filter the
water through a coffee filter before pouring the water into the
What are some of the water sources I can filter through the Portable LP2 British Berkefeld® gravity model?
Water from ponds, creeks, lakes, rivers, wells, cisterns, rain, or
even water you have stored yourself can be used for drinking and cooking
with peace of mind.
How does the Portable LP2 Berkefeld® compare to other types of water filtration systems?
Inline Systems: Berkefeld® works with no water pressure, while
inline systems need innovative adaptation if you do not have water pressure
How do the Berkefeld® gravity models work?
Just add water into the upper chamber.
Gravity causes the water to flow through the filters to
the lower chamber. A 4-filter system using 7" filters
will produce about a gallon per hour. Using 4 10"
filters will produce about 1.25 gallons per hour.
Why do the ceramic elements contain silver? Are they safe?
In a multilayer candle, the protective effect is
even more critical because carbon is a natural growth medium for
bacteria. In carbon-only filter elements, which are commonly found,
the carbon filter often ends up as being a bacteria repositary if
not changed regularly.
What types of bacteria, chemicals and metals are removed or reduced by Arkwater.com's Doulton® filters?
are heterotrophic bacteria?
Some are good bacteria, for example, the probiotics and prebiotics as discovered by Nobel prize winner Eli Metchnikoff. These include bacteria found in yogurts, 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). Within a water context, the presence of these pathenogenic 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 of presence makes them a good indicator organism for faecal contamination. The specific measurement of E Coli in water, (as opposd to all heterotrophic bacteria), has become the prescribed way to measure the safety of drinking water.
Arkwater.com’s Doulton drinking water filters reliably remove more than 99.99% of pathogenic bacteria, producing potable water as a result.
is HPC (Heterotrophic Plate Count)?
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 maybe some bad people. The HPC is like measuring the presence of people in an area and then concluding that, since there are people, perhaps there may be bad people within this group of people.
Of course this is not a good method to measure bad people. There are many small communities everywhere which would claim the absence of any really bad people.
A better way to measure bad people is to look at the crime statistics - sort of like what the E Coli tests are about. Which 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.
In a similar way, 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 bad elements within that population with certainty.
Heterotrophic Plate Count (HPC) and gastrointestinal illness)
According to the World Health organisation, a study was conducted among Navy 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 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 difference between people receiving water with high HPC and unfiltered water (low HPC) .
A futher study was conducted in 1991 and came to the same conclusion (Calderon and Mood 1991)
A further trial was conducted by Payment in 1997 (Payment 1997) with 4 groups of people; those drinking tap water, those whose tap was left running so the water was wasted, those given bottled plant effluent water and those given plant effluent water further treated by reverse osmosis (RO).
In the 2 groups using bottled plant effluent water, there was significantly higher HPC. Despite this, the gastrointestinal illness rates were not significantly different between the 2 groups. With regard to the 2 “taps” groups, the illness rate in the group with continual running water tap (lower HPC) was actually higher.
The Wolrd Health organisation concludes that the studies demonstrate there is no association between counts of HPC bacteria and gastrointestinal illness in humans.
water filtration systems breed Heterotrophic bacteria?
However, because activated carbon is a chlorine adsorber, there is a disinfection mechanism because chlorine kills bacteria and suppresses bacterial growth; which is why it is introduced into the municipal water supply. So as the activated carbon extracts the chlorine from the water, there is a suppression of the bacterial growth.
However, should the influent water not be chlorinated as in some countries, the activated carbon will breed heterotrophic bacteria. Nevertheless, this is still not an issue because the activated carbon is after the ceramic filter, the benign bacteria that inhabit the activated carbon arrive there through the unavoidable contact with the environment. But pathenogenic bacteria that would come through fecal copntamination of the water supply are blocked by the filter.
Therefore, where there isn't a chlorinated municipal supply, the HPC results could certainly be higher after passing through the filter...
systems always provide significant (99.99%) reduction of microbial
pathogens even in cases where tje HPC measurement may even show an increase
relative to the filtered water. HPC
measurements do not correlate to the concentration of pathogenic
bacteria., i.e. the safety of the water.
In fact, some studies suggest that residual HPC bacteria may demonstrate a protective effect, by competing with pathogenic bacteria. This effect is used in slow sand filters, where the Schmutzdecke, a biologically active film formed on the surface of the sand filter and containing a massive amount of heterotrophic bacteria, is used to detroy pathenogenic bacteria.
water with a high concentration of HPC bacteria present any concern to health?
Heterotrophic Plate Count (HPC) was the earliest tool of bacteriology starting in the late 19th century, but by the mid 20th century, science had advanced to a point where it was realised that although it could be used as a proxy indicator, a high plate count was not an indication of the safety of water.
The United Kingdom Ministry of Health provided formal guidance on the bacteriological examination on water supplies.that was known as "Report 71" and according to the World Health organisation, by the 5th edition published in 1982, "all reference to the use of HPC to potentially indicate faecal contamination had been dropped"
Even commercial bottled water has been found to contain high levels of heterotrophic bacteria.. These reach a HPC bacterial count of 7300 cfu/ml (colony forming units per millilitre). Even famous brands , contain some level of "colony forming units"
Arkwater water filtration removes over 99.99% of harmful microbial pathogens, meaning that even if there is a high HPC measurement, the water is perfectly safe to drink. Arkwater or any filtration systems with activated carbon will show HPC counts.
Sterile water stored in
sterile packages like those used in intravenous drips in hospitals, are free of
HPC bacteria. Other foodstuffs often have an extremely high HPC measurement; for example, a
measurement taken from carrots and lettuce gave a reading of about 1,000,000
According to the 2003 World Health Organisation Expert Consensus on HPC and Drinking Water Safety, there is no evidence that HPC values alone directly relate to health risk.
can HPC bacteria be inactivated or removed completely from water?
If heterotrophic bacteria are totally undesired, consumers may boil or UV steralise water after filtration. In this case, it is better to boil the water immediately before drinking, as water left to stand may also begin to breed heterotrophic bacteria. Normal tap water left overnight will show high HPC.
The age-old tradition of boiling drinking
water kills or otherwise inactivates microbial pathogens, but the water must be
boiled for at least ten minutes to be considered sterile. However, boiling unfiltered water does not
remove chemical toxins and in fact, can concentrate these.
Chlorine is a disinfectant and when added
to water, it kills bacteria. Chlorine
however may sometimes not be an effective treatment against Giardia cysts. Alternatively, irradiation by ultraviolet light destroys DNA, hence killing
bacteria, viruses, and any pathogens.
However, none of these methods of
boiling, chlorination or irradiation, will remove suspended particles or
dissolved chemicals (chlorine, pesticides) or dissolved heavy metals (copper,
lead), and thus simple boiling may still produce water undesirable for
For Arkwater filtration systems, if HPC is an issue, the customers can opt for a plain ceramic filter on its own without activated carbon . However, this will mean that chlorine and other harmful chemicals like Trihalomethanes will not be removed. An option to deal with that would be to have a multistage filter with the activated carbon before the ceramic filter.
This is done in Arkwater's rural and community systems (RS6 and CS4 systems) - multistage systems that have activated carbon before the microfiltration stage and utilise post filter UV steralisation.
Arkwater.com can provide UV steralisation if required. Optional activated carbon / nano silver cartridges may be used to minmise HPC.
Will Doulton be around in 5,10, or more years' time, for me to get spare parts for the Doulton® purifier?
You can trust Doulton®.
Doulton first entered the water filtration business serving the industrial sector. Doulton® now brings its advanced technology to residential homes.
Doulton®'s filter technology has been time-tested and proven over 150 years of continuous product research and development since 1827 when Henry Doulton first created ceramic filters to remove harmful bacteria from drinking water.
Worldwide, Doulton® is one of the most reliable and trusted brand. Doulton® filters are not only being used by families in residential homes, it is also used by bottling companies, hospitals, clinics, and many other industrial companies for water filtration processes.
Doulton® is also used by the International Red Cross, Unicef, Save the Children, embassies and field workers in over 150 countries worldwide.
Warranty: All British Berkefeld® and Doulton® filter housings have a one-year warranty against factory defects. As is the market practice, this factory guarantee is invalid for damage, breakage, spoilage, etc. caused by poor handling.
Arkwater.com's management has toured the
Doulton® factory in England.
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