a) pH :
Before pH can be convincingly discussed, one must firstly survey the
fundamental properties of water. We fill
our pools with it; we wash our clothes with it; we even power generators with
it; but many uninformed pool and spa owners underestimate its solvency
potential. Water is composed of two
hydrogen atoms covalently bonded to one oxygen atom. The result is water or H2O. But theres much more than just water in
water. Water dissociates similar to
hypochlorous and hypobromous acids. The
following chemical equation represents the dissociation of water. This dissociation generate hydrogen and
-----------H+ (Hydrogen Ion) + OH- (Hydroxide Ion)
hydrogen ion concentration determines the pH. The greater the hydrogen ion concentration, the lower the pH, and the
more acidic is the water. Decreasing the
hydrogen ion concentration increases the pH and reduces the waters
acidity. A neutral pH exists when the
hydrogen ion (H+) concentration is equal to the hydroxide (OH-) ion
concentration. A pH of 7 is termed
neutral; below 7 is acidic; above 7 is basic.
b) Total Alkalinity : Total Alkalinity (TA) is the quantitative
measurement of alkaline components present in water to act as a buffer against
rapid pH changes. Proper TA levels are
important to ensure optimum chemical balance in pool, spa and other aquatic
systems. Low TA is frequently
coincidental with green water, plaster etching and accelerated corrosion
rates. If too high, TA should be lowered
by the addition of acid. For effective TA reduction, the acid should be added
in its concentrated form.
c) Calcium Hardness (CH) : Calcium hardness indicates the calcium (Ca+2) content of water usually
as milligrams/liter (mg/l) or ppm. Not
to be confused with Total Hardness, which is the sum of calcium and magnesium,
calcium hardness is the primary parameter that dictates water balance. Too high causes scale formation, filter
calcification, heater inefficiency, reduced circulation, rough pool/spa
surfaces and eye irritation. Too low
causes etching of plaster, aggressive (corrosive) water, surface pitting and
premature heater failure.
d) Total Dissolved
solids (TDS) : Total dissolved solids is an electrochemical
measurement of a waters ability to conduct an electrical current. The electrical conductivity increases with
increasing TDS or the presence of dissolved (charged) chemical species in the
water. TDS is a semiquantitative
measurement of a waters dissolved ion content. As TDS increases, so does the buildup of unoxidized or partially
oxidized organic and nitrogenous contaminants from swimmer/soaker wastes and
other sources. High TDS can enhance
algae growth rates, increase natural (galvanic) corrosion, accelerate
staining and scaling of pool and spa surfaces.
In addition to maintaining proper levels, a daily water replacement
policy optimizes the potencial for good water quality resulting in a safer,
more enjoyable swimming or soaking experience.
e) Temperature : According to the Langelier Saturation Index, five primary factors effect
water balance and are therefore incorporated into the saturation index
formula. They include; pH, calcium
hardness, total alkalinity, temperature and total dissolved solids.
·The algae are the simplest
member of the plant kingdom.They are
microscopic, single-celled forms of plant life that exist in virtually all
surfaces water and most ground water.Their widespread presence and unrestricted transmission modes creates a
strong tendency for contamination of swimming pools and spas.Even the best maintained swimming pool can
experience algae problems.
·Algae have no leaves, stem,
roots or vascular system.It is
estimated that their exists approximately 18 000 species of algae of
marine or fresh water origin.Although
their presence in recreational aquatic systems is aesthetically undesirable,
algae in natural ecosystems play a positive role; some scientists believe that
90% of all photosynthetic activity, and thus vital oxygen generation, is
carried out by algae.
·Algae growth is stimulated by
hot weather, sunlight, heavy bather loads, and insufficient disinfectant
level.Scale formation and surface
deposits can facilitate algae growth by creating an ideal surface for algae
·Generally speaking, algae is
not harmful to swimmers.But from a
safety viewpoint, algae should be considered as a potential hazard.Untreated surface-clinging algae can turn a
pool bottom and its sides into a slippery mat increasing the likelihood of
personal injury from slips or falls.Algae growth frequently causes turbid water and darkened pool surfaces
making it difficult to see swimmers in distress.
·Prevention is by far the most
effective and least costly when dealing with algae. Respond immediately to ANY
sign of algae growth.See Bioguard link
for BackUp and 3-Step System.
·One of the most frequently
encountered problems in pools and spas is cloudy water.Residential pool owners curse it; commercial
pools are closed because of it; and spa owners detest soaking their bodies in
it.Cloudy water is definitely a
·Most often treated as a
chemical imbalance problem, cloudy water concerns should be first addressed by
careful observation of the filtration / recirculation system.Therefore, when dealing with cloudy water,
begin with the physical aspect of water treatment followed by the chemical
·Questions that the person that
will be testing your water in the shop, will ask you will be the following; Is
the pool or spa indoor or outdoor?, Bather load per day?, What is the total
water volume of the system?, Is the filtration system properly sized? ( Many
cloudy pools and spas have been successfully cleared by simply installing a
properly sized filter.), What is the condition of the filter media? (when was
the sand last changed or cleaned with StripKwik).
·The chlorine demand of water is
the difference between the amount of chlorine applied and the amount of free,
combined or total available chlorine remaining at the end of the contact
period.Chlorine demand is caused by
inorganic minerals such as Ferrous (Fe2+), manganous (Mn2+), ammonia, amino
·Combined Available Chlorine
(CAC) also known as chloramines, CAC are the undesireable compounds formed when
insufficient levels of free available chlorine chemically react with ammonia
and other nitrogenous compounds.
·Breakpoint Chlorination will be
needed.It is the process of adding
sufficient free available chlorine (FAC) or other oxidant to chemically convert
chloramines and ammonia-nitrogen compounds to inert nitrogen gas (N2).