Q1) When does a
ceramic filter element need cleaning?
A1) Once the flow out of the filter becomes noticeably less than
normal.
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Q2) How do I clean a filter candle?
A2) Use a scouring pad (similar to 3M “Scotchbrite”). Ensure
that the end of the plastic mount does not come into contact
with unfiltered water and dirty hands. Rubber gloves are
recommended to be used during cleaning and NEVER use soap or
detergents!
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Q3) My filter candle blocks up too regularly, what can I
do about it?
A3) In some water conditions, there is so much particulate or
turbidity in the water supply that the filter element becomes
blocked much quicker than in normal conditions. In these
circumstances, it is beneficial to use a pre-filter upstream of
the ceramic candle. This prevents the candle from becoming
blocked too quickly, minimises cleaning and so extends the life
of the ceramic filter.
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Q4) When does a ceramic filter element need replacing?
A4) This depends on the type of candle being used:
Sterasyl™
Should be replaced once cleaning fails to restore the water
flow. However, we usually recommend that Sterasyl™ candles are
replaced after 10,000 litres of water have passed through the
candle, to guarantee optimum performance.
Super Sterasyl™, Carbosyl™, Supercarb™, and
Ultracarb™
In combination filter elements (ceramic shells containing other
types of filter media) cleaning the ceramic will not extend the
life of the internal material. For example, the ‘life’ of the
carbon block in Supercarb™ or Ultracarb™ filter elements is
determined by the concentration of chlorine and/or volatile
organic compounds in the water supply. The particulate and
turbidity concentration in the water supply govern the life of
the ceramic. This means that the life of the ceramic might or
might not exceed the capacity of the carbon insert, depending on
the water quality. Whichever point is reached first – the six
months usage or the ceramic becoming blocked to the extent where
cleaning does not restore the flow – governs when the filter
element requires replacing.
In most cases, the filter element should be
replaced after 6 - 12 months of daily use. The following flow
guidelines can be used to guarantee optimum performance:
Super Sterasyl™ 2,000 litres or 535 US gallons
Carbosyl™ 1,496 litres or 400 US gallons
Supercarb™ 3,740 litres or 1000 US gallons
Ultracarb™ 2,244 litres or 600 US gallons
After this amount of water has passed through
the filter element, the filter will need to be replaced to
guarantee optimum performance.
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Q5) I don’t have a flow meter to gauge the amount of
water that my filter has treated. How can
I estimate how much water has passed through the filter?
A5) On average a family of four uses approximately 8 litres of
water per day for cooking and drinking. Therefore, based on 10
litres/day for four people the life of your filter can be
estimated in time rather than capacity.
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Q6) Do I need to sterilise the candle after cleaning?
A6) The ceramic shell of Sterasyl™, Super Sterasyl™, Carbosyl™,
Supercarb™, and Ultracarb™ filter elements all contain trace
amounts of silver to prevent microbiological growth. These
elements are self-sterilising and should NOT be sterilised after
cleaning. In the case of combination filter elements, boiling
will damage the internal components of the element.
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Q7) How do I keep my filter housing clean?
A7) The filter housing is best cleaned by unscrewing the body
from the head and wiping the surface and the inside of the body
with a soft cloth dampened with warm water.
IMPORTANT – DO NOT ATTEMPT TO CLEAN THE FILTER HEAD, WHICH COULD
CAUSE CONTAMINATION OF THE FILTERED WATER.
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Q8) What happens if I leave the filter unused for a
period of time?
A8) If normal use of the filter is interrupted by holidays or
vacations, growth of harmless heterotrophic bacteria may result
in a ‘flat’ or ‘stale’ taste for a period of time when use of
the filter resumes. This is especially true for the filter
elements that contain activated carbon such as the Super
Sterasyl™ (contains granular activated carbon), the Supercarb™
and Ultracarb™ (both contain an extruded activated carbon core).
Flushing the filter system for several minutes after any
prolonged period of inactivity should eliminate the problem.
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Q9) What is the
difference between temporary and permanent hardness in water?
A9) Hardness caused by the presence of positively charged metal
ions. Total hardness is measured as the equivalent of milligrams
per litre of calcium carbonate. Temporary hardness only contains
metal carbonates and bicarbonates, the most typical being
calcium carbonate. Temporary hardness is precipitated from water
when heated and is responsible for the furring of heating
elements and metal pipes. Permanent hardness consists of
non-carbonate based metal salts, and does not precipitate out on
heating.
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Q10) Will my Doulton® or British Berkefeld® filter
element remove hardness?
A10) Unfortunately filtration does not remove hardness from
water so Doulton® or British Berkefeld® filter elements will not
affect the hardness in drinking water. Hardness can be removed
by water softening, deionisation or magnetic and electrical
conditioning devices.
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Q11) Will hardness affect the performance of an
Ultracarb™ filter element?
A11) The ATS media used in our Ultracarb™ filters will adsorb
lead, even in the presence of calcium and magnesium ions. This
is proven in the NSF certification testing. One of the test
protocols for metal(s) reduction calls for testing at high pH,
high TDS conditions to simulate use in hard waters. Filter
elements containing ATS have to pass this part of the test
protocol before they can receive NSF certification.
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Q12) Will my Doulton® or British Berkefeld® filter
element remove Aluminium?
A12) The Doulton® and British Berkefeld® range of ceramic water
filters are only suitable for the removal of aluminium in
particulate form. They are not proven to be suitable for
treating dissolved aluminium. To treat water containing soluble
aluminium, ion exchange resin, distillation or reverse osmosis
must be used.
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Q13) Will my Doulton® or British Berkefeld® filter
element remove Arsenic?
A13) No, Arsenic is likely to be in a dissolved state, to remove
arsenic passage through activated alumina is the best method.
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Q14) Will my Doulton® or British Berkefeld® filter
element remove all types of
bacteria?
A14) No. The large number of different species of bacteria of
different shape, size and growth characteristics, preclude the
ceramic filter from being effective against all of them.
The pathogenic bacteria that FICL claim to be
effective against have been qualified by test data from
independent test laboratories or are extrapolated from test data
of similar microorganisms (please seek advice from FICL on
permitted extrapolated claims).
Although the ceramic will filter all types
of heterotrophic bacteria to some extent, it should be noted
that any harmless bacteria of this type passing through the
ceramic may multiply downstream of the filter. Since these
heterotrophic bacteria are harmless, normally there are no
problems and some heterotrophic bacteria are reported to be
beneficial to health. However, if normal use of the filter is
interrupted by holidays or vacations, growth of these bacteria
may result in a ‘flat' or ‘stale' taste for a period of time
when use of the filter resumes. This is especially true for the
filter elements that contain activated carbon such as the Super
Sterasyl™ (contains granular activated carbon), the Supercarb™
and Ultracarb™ (both contain an extruded activated carbon core).
Any system containing activated carbon, which will reduce
residual levels of free chlorine, will result in an increase in
plate counts over a short period of time until a constant state
of equilibrium is established. The UK Drinking Water
Inspectorate water regulations call for the water to be
regularly monitored for consistency as used, therefore since an
equilibrium point is reached in the filtered water, the filters
comply with the regulations. The presence of this type of
heterotrophic bacteria does not constitute a health problem
since the organisms present will be harmless and a suitable
level of consistency would be established. Flushing the filter
system for several minutes after any prolonged period of
inactivity should eliminate the problem.
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Q15) Will my Doulton® or British Berkefeld® filter
element remove Chloramine?
A15) Chloramine may be removed by passing through a bed of
activated carbon, but requires much greater contact time with
the carbon than chlorine, so a slow flow rate through the carbon
must be ensured. Unfortunately although the Doulton® or British
Berkefeld® Super Sterasyl™, Carbosyl™, Supercarb™, and Ultracarb™
filter elements contain activated carbon, they may reduce levels
but will not remove chloramine because there is insufficient
contact time with the carbon.
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Q16) Will my Doulton® or British Berkefeld® remove
diesel, petroleum or MTBE?
A16) The ceramic part of our filter elements will not take out
any of these organic materials. The activated carbon in the
Supercarb™ and Ultracarb™ filter elements will have some effect.
However, to remove these types of materials requires much
greater quantities of activated carbon and much longer contact
time than our filters can provide.
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Q17) Will my Doulton® or British Berkefeld® filter
element remove Fluoride?
A17) No. Fluoride salts are soluble in water. To remove
dissolved fluoride, passage through activated alumina is the
best method.
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Q18) Will my Doulton® or British Berkefeld® filter
element remove Iron?
A18) The Doulton® and British Berkefeld® ranges of ceramic water
filters are only suitable for the removal of iron in particulate
form. They are not proven as suitable for treating dissolved
iron. To treat water containing soluble iron, the iron must be
oxidised to induce precipitation prior to filtration.
Alternatively distillation or reverse osmosis can be used.
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Q19) Will my Doulton® or British Berkefeld® filter
element remove Legionella?
A19) Since Legionella has a similar morphology to E-coli, our
ceramic filter elements should provide similar protection
against Legionella . However, Legionella is capable of slow
regrowth downstream of the filter, so if just one organism
passes through the ceramic it could eventually colonise the
water delivery system. Therefore it is important to regularly
disinfect downstream of the filter or fit a UV light just after
the filter.
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Q20) Will my Doulton® or British Berkefeld® filter
element remove Manganese?
A20) No, to remove Manganese, oxidation treatment and filtration
can be done, or for low levels of contamination, Green sand or
Inversand can be used.
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Q21) Will my Doulton® or British Berkefeld® filter
element remove Nitrates?
A21) Unfortunately the ceramic filter elements will not remove
nitrates. In the home the only effective method that can be used
to remove nitrates is ion exchange media.
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Q22) Will my Doulton® or British Berkefeld® filter
element remove Oestrogen and
Synthetic Oestrogen?
A22) There has been a limited amount of research into Oestrogen
and Synthetic Oestrogen, and so we do not have quantifiable test
data on the effectiveness of our products in removing it. Due to
the chemical properties of Oestrogen, we believe that activated
carbon would be effective in reducing it. However until better
test methodology is available, we are unable make a claim.
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Q23) Will my Doulton®
or British Berkefeld® filter element remove Pseudamonas
aeroginosa?
A23) Pseudomonas aeroginosa is a potential coloniser of water
system networks and is similar in size to E-coli. FICL candles
should therefore, in theory, show a similar reduction efficiency
for Pseudomonas aeroginosa as for E-coli. However, since this
organism is rapid growing and may recover quickly, without
physically testing FICL ceramic filters with this type of
organism, it is impossible to predict a performance claim. FICL
is not prepared to attempt a prediction of performance, since
the filters provide a <99.99% barrier, but do not provide 100%
barrier to E-coli. A limited number of cells may pass through
the filter which, unlike E-coli, may form colonies down stream
of the filter. It would be more suitable to combine filtration
with a disinfection stage to ensure removal of Pseudomonas
aeroginosa.
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Q24) Why does the pH of
my drinking water increase when I use my ceramic filter?
A24) The slight increase in the pH of water passed through the
ceramic filters is due to the presence of the mineral
Wollastonite in the ceramic. Wollastonite is slightly soluble
and alkaline, so may partly dissolve in the water as it passes
through the filter causing a minor pH shift which is harmless.
No health based guideline value for pH in drinking water has
been proposed by the WHO, although accompanying notes to the
guidelines state that the pH range is often in the range of
6.5-9.5. In general there is little evidence to suggest that pH
in potable water of around 9-10 is of public health
significance.
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Q25) What level of
bacterial contamination can the ceramic cope with before I need
to use something else?
A25) In the absence of conclusive data regarding the levels of
infective doses for specific pathogens, the FICL microbiological
laboratory has been testing our filter elements for many years
using an influent challenge of 6 log of E-Coli to substantiate
the 4 log E-coli reduction claim that we make. This level of
protection offered by the filters is more than adequate in all
protected waters and the vast majority of moderately
contaminated surface waters. However, if the level of
contamination in the water exceeds levels of 104
(4log) an additional treatment must be used
such as disinfection or UV light treatment. It would be
extremely unusual for water having a greater level of
contamination than 104,
to be considered suitable as a potable water source.
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