Q. Why do I need chemicals in my pool water?
A. You need a sanitizer in the water, usually chlorine or bromine, to kill
bacteria, bugs etc. that accumulate from bathing and the outdoor environment.
The more the pool is used and the warmer the weather, the more sanitizer will be
required. This is referred to as the "chlorine (or bromine) demand".
PH balance chemicals are required to neutralize the acidity/alkalinity of the
water.
Q. With my small above ground pool, why can't I simply replace the water with
fresh tap water every few days when it goes green? I don't want to expose my
children to unnecessary chemicals.
A. Apart from the obvious environmental issues, particularly with the
current water shortages in many areas. Tap water is only clean when it leaves
the tap or hosepipe. Ask yourself this…Would you take a bowl of water, sit
several people in the bowl, (perhaps small pre potty trained children), for
several hours, bathing their nether regions, feet etc. and then drink or rinse
your mouth around with that water?? And don't forget, birds fly over your pool,
insects die in it, and the general accumulation of dirt in the air. Sanitation
chemicals are not perfect, but they are the better of two evils. Unsanitized
water can be dangerous.
Q. Why does the PH alkalinity have to be balanced?
A. Using Chlorine etc. tends to affect the PH balance of the water over
time. Natural conditions such as the water supply, leaves etc. also change the
balance. Incorrect balance will prevent the sanitizer from working correctly. It
can also be corrosive to the pool equipment such as the pumps and ladders.
Unbalanced PH levels can irritate skin and eyes. Unbalanced pool water can
sometimes reach the acidity (low PH) of a lemon or even higher to that of
battery acid in extreme cases!!
Q. What is "total alkalinity"
A. TA measures the Carbonates and Bicarbonates in the water. This can be
thought of as the water's ability to change PH. A sort of, "available PH if
you like. Chemicals referred to as "TA plus" and "TA minus"
can be used to correct this imbalance. Poor TA balance is often the result of
insufficient water refreshment due to poor cleaning and not enough "vac to
waste"
Q. What does "refreshment" mean
A. Removing some of the pool water, perhaps a third, and replacing with
clean tap water.
Q. Why do I find it difficult to balance my PH.
A. This is usually due to high or low levels of TA. The PH tends to bounce
from one extreme to another. Refreshment is also recommended.
Q. Is there an alternative treatment for water if I have an allergy to
Chlorine?
A. Chemical levels can be reduced by using some of the electronic methods
available. Such as salt-water chlorinators, UV sterilisation or electromagnetic
devices.
Salt-water chlorinators are becoming more popular. They work by adding a little
salt to the water, (less than seawater, about as salty as a teardrop, some folk
can't taste it at all) and passing a tiny, safe, low voltage, electric current,
via electrodes to the salt water. As chlorine is a product of salt, (sodium +
chlorine) chlorine is manufactured in the device, but at a lower level. Modern
Chlorinators tend to be self-cleaning (by reversing the electrical polarity) and
don't suffer as much as they used to from corrosion.
UV Sanitation is achieved by exposing the water to high
levels of UV light as it passes through a tube. With this method, a much lower
level of sanitizer is required.
Some electromagnetic devices claim that no chlorine is required. We recommend
that the manufacturers instructions be followed.
Bromine is an alternative sanitizer chemical to chlorine. It is more expensive
but does not tend to irritate sensitive skin as much. Bathers with skin
conditions such as eczema and psoriasis usually find it better. A non-chlorine
shock should be used instead of normal chlorine shock.
Q. What is the difference between; liquid, granuals,
tablets and shock chlorine?
A. All chlorine types disassociate in water into hypochlorous (HOCL) and
hydrochloric (HCL) acids. These are the active sanitizers, also called
"free chlorine"
Liquid chlorine (sodium hypochlorite 10 to 15%) is poured evenly, directly into
the pool water, where it forms NAOCL. Calcium+ Chlorine+ Oxygen. Most of the
liquid turns into "free chlorine" with not much "available
chlorine" and therefore does not tend to last long, although this does mean
that it can be used as a shock treatment. It is bulky and not easy to store. It
has a short shelf life of around 6 months, continuously reducing in strength. It
should be kept in the dark.
Chlorine Granules are higher in concentration, typically 60% of active
sanitizers, they can be spread evenly over the surface of the water (try the
pinch test. A pinch of grans is sprinkled into the shallow end and if they
dissolve before they reach the bottom, then they can be added directly into the
water as they are, but if they settle on the bottom, then pre- dissolve them in
hot water). Granules vary in chemical make up depending on the amount of
stabilizer they contain. The stabilizer increases the amount of "available
chlorine" in the water. Although the granules themselves dissolve, the
available chlorine is a slow release process, which enables the level to be
maintained for a longer period.
Chlorine tablets are simply compressed tablet forms of
granules
Multi function tabs or granules have other chemicals mixed in them for better
water quality. These are usually, Algaecide and Flocculent.
Shock chlorine: Using chlorine at the "comfort zone" level of between
1& 3 ppm does not entirely kill all the bacteria etc that can build up
immunity to such levels over a period of time. Shock doses of chlorine are used
every 2 to 4 weeks to raise it to about 10ppm, which will totally sanitize the
pool. Unlike normal stabilized chlorine, shock has very little "available
chlorine" and will therefore reduce much quicker. It is better to wait
until the levels have dropped down to at least 5ppm before you use the pool
again.
Q. I cannot get any stability with my chemicals.
A. After some time, impurities build up in the water and increase the TDS
(total dissolved solids) levels in the pool. This can be thought of as the
"hardness" of the water. Some consider that at this time the water is
said to have "died" The easiest solution to this is partial or total
refreshment. If you are in a very hard water area, you may want to take further
advice from an expert!
Q. What is flock?
A. The pool filtration either sand or cartridge, filters small particles
down to approximately 3 microns. Smaller particles pass through the filter and
return to the pool causing the water to be cloudy. Flocculants sometimes
referred to as "clarifiers" stick these particles together enabling
the filter to capture particles down to about one micron, producing clearer
water. The flock also caused these particles to sink to the bottom. They are
then removed by a "vac to waste" this may have to be repeated over a
period of several days.
Q. Why use Algaecides as well as a sanitizer?
A. Although Chorine use alone, at the upper end of the comfort zone (1 to 3
ppm) will inhibit the growth of algae, the use of an algaecide in conjunction
with chlorine is better.
http://www.howardswimmingpools.co.uk (+44) 01344 873323