A:
ACID
A sour chemical substance containing hydrogen with the ability to
dissolve metals, neutralise alkaline materials and combine with
bases to form salts. Acid is used to lower (decrease) pH and
total alkalinity of swimming pool and spa water. Examples are
muriatic acid (hydrochloric) and dry acid (sodium bisulphate).
ACID DEMAND:
The amount of acid required to bring high pH or total alkalinity
down to their proper levels. Determined by an acid demand test.
ACID DEMAND TEST:
A reagent test usually used in conjunction with a pH test to
determine the amount of acid needed to lower pH or total
alkalinity.
ACID RAIN:
Precipitation having a low pH value
caused by air polluted with sulphur dioxide, carbon dioxide or
nitrous oxide.
ACTIVE BROMINE
Bromine which is readily available for killing bacteria and algae.
It is measured by DPD No 1 test tablet and includes free bromine
and some bromamines.
AIR BLEEDER ASSEMBLY:
See Air-Relief Valve
ALGAE:
Microscopic plant-like organisms that contain chlorophyll. Algae
are nourished by carbon dioxide (CO²) and use sunlight to carry
out photosynthesis. They find their way into the pool by rain or
wind and grow in colonies, resulting in algae blooms. Algae do
not cause disease, but provide an ideal substrate for bacteria to
thrive in. There are over 21,000 known species of algae. The
most common pool types are black algae, blue-green algae, green
algae and mustard algae. Pink algae or red algae-like organisms
can be found, but are in fact bacteria. Maintaining proper
sanitiser levels, shock treatments and superchlorination will help
to prevent or destroy algae.
ALGAECIDE:
Meaning to kill algae. Algaecides perform best as a backup to a
routine sanitation program. They also help to kill airborne
spores as they blow into the pool. A variety of algae treatment
products are available including copper and silver compounds, quat
compounds, chlorine enhancers and herbicides. Algaecides are
often formulated for a specific type of algae (green algae,
mustard algae, black algae) with black algae being the hardest to
treat.
ALGAESTAT:
An algaecide kills algae, while an
algaestat retards and prevents its development and growth.
ALGEA:
See Algae
ALGICIDE:
See Algaecide
ALKALI:
Also called a Base. An alkali is the opposite of acid and is used
to increase the pH or total alkalinity of swimming pool water.
Most common are sodium carbonate or sodium hydroxide to increase
pH, and sodium bicarbonate to increase total alkalinity.
ALKALINITY:
Also called Total Alkalinity. A measure of the pH-buffering
capacity of water or the water’s resistance to change in pH. It
is composed of the hydroxides, carbonates and bicarbonates in the
water. When we measure the total alkalinity, we usually only
measure the carbonate alkalinity level.
ALUMINUM SULPHATE:
Also known as Alum. This product is used as a flocculant which
attracts suspended particles in the water to each other. Alum
sinks everything to the bottom, which can then be vacuumed to
waste. A small amount of alum can also be used as a sand filter
additive.
AMMONIA:
(NH³) It is a nitrogen-containing compound introduced into the
water by swimmers as waste (perspiration or urine) or by other
means. It quickly combines with chlorine to form bad-smelling
chloramines, which are harmful to our health.
AMPEROMETRIC:
This is a method of determining chlorine levels often used in
automatic controllers incorporating either platinum/platinum or
platinum/copper electrodes.
AMPEROSTATIC:
(Potentiostatic) A method of measuring chlorine residuals used in
automatic controllers using platinum/gold electrodes.
ANTI-FOAM:
A chemical added to the water to reduce the foam. These products
do not remove the source of the foaming. Shocking and
superchlorination may help prevent foaming. Careful use of
cheaper algaecides/algaestats can prevent foaming.
ASCORBIC ACID:
A chemical compound used to remove iron stains from fibreglass and
vinyl-liner pools.
AQUABROME:
Trade name for dry organic compound
1-Bromo-3¨-chloro-5.5-Dimethyldantoin, a bromine based swimming
pool disinfectant.
AUTOMATIC POOL CLEANER:
A pool maintenance system that will brush or vacuum dirt and
debris from the interior of the pool automatically. Some cleaners
work on low-voltage electricity, others on the pump’s suction line.
The pool cleaner may be programmable, automatic or may move
randomly around the pool. Some cleaners can climb the walls of
the pool, while others only clean the floor.
AVAILABLE CHLORINE CONTENT:
A term used to compare the amount of oxidising power that chlorine-containing
products have when compared to gas chlorine (Cl²). It permits
easy comparison of relative values of chlorine compounds.
AVAILABLE CHLORINE:
The amount of free chlorine that is available to sanitise or
disinfect the water. It is also called Residual Chlorine and Free
Available Chlorine.
B:
BACKFILL:
The repositioning of the soil after
construction of a pool
BACKFLOW:
The back-pressure of water in a
pipe in the opposite direction to normal flow
BACKWASH:
Thoroughly cleaning a sand filter
by reversing the flow of water through it so that the dirt and
rinse water go to waste. When the pressure gauge indicates, you
will need to backwash the filter. When the handle is turned to
backwash, the flow through the filter is reversed, say, bottom to
top. The effluent water (out of the filter) is directed to the
waste line
BACTERIA:
Unicellular micro-organisms of
various forms. Some are pathogens, which can cause infectious
diseases. Bacteria are controlled by chlorine, bromine or other
sanitisers or disinfectants
BACTERICIDE:
Meaning to kill bacteria. It is a
chemical (e.g. chlorine) or an element (e.g. silver) that kills
bacteria
BAKING SODA:
Chemically, Sodium Bicarbonate. It
is white powder used to raise the total alkalinity of pool water
without having much effect on pH. It will only increase pH up to
8.5, regardless of the quantities used. Care should be taken,
however, to avoid adding large quantities at one time
BALANCED WATER:
Balanced water is the result when
all of your chemical parameters are within the tolerance limits.
The most important parameters of water balance are pH, Total
Alkalinity, Calcium Hardness and Temperature, as measured using
the Langelier Saturation Index
BALL VALVE:
A device with a hollowed out ball
inside which can be turned with an external handle to decrease or
increase flow
BASE:
Chemicals of alkaline nature which will counteract the pH of an
acid. Common bases used around the pool include Soda Ash, Sodium
Bicarbonate and Sodium Carbonate. A base is the opposite of an
acid. See Alkali
BASE DEMAND:
A titration test used to determine
the amount of base (alkali) required to increase the pH to the
correct level
BATHER LOAD:
The number of individuals using a
pool in a 24 hour period and the pool’s principal source of
bacterial and organic contamination
BCDMH:
Chemically, “bromochlorodimethylhydantoin”,
it is a bromine sanitiser. When BCDMH dissolves in water it
produces Hypobromous Acid and Hypochlorous Acid
BICARB:
See Sodium Bicarbonate
BIGUANIDES:
The name for a certain class of
sanitisers using the polymer PHMB, the only non-halogen sanitiser
available for pool use. Soft Swim and Baquacil are manufacturers
of this sanitiser. Buguanides are NOT compatible with the Pool
Wizard
BLEACH:
This term usually refers to liquid
chlorine. It is the same chemical used in the home, but pool
chlorine (sodium hypochlorite) has 12%-15% available chlorine
while laundry bleach only has about 5% available chlorine
D:
DECHLORINATION:
The process of chlorine removal (usually
by the addition of sodium thiosulphate) when too much chlorine has
been added to the pool.
DE FILTER:
A filtration system that uses a
layer of fine powder (diatomaceous earth) to remove contaminants
from the water. This type of filter requires a ten minute
backwashing process about once a month that is accomplished by
adjusting the valves. The DE powder is relatively inexpensive but
must be replaced after each back washing.
DEFOAMER:
Also called anti-foam. A chemical
added to the water to destroy the foam. These products do not
remove the source of the foaming. Shocking and superchlorination
may help prevent foaming.
Most often,
the water must be drained and refilled to remove the soaps, oils
and other causes of foaming.
Controlled use of certain of the cheaper algaecides can prevent
their resulting in foaming.
DIATOMACEOUS EARTH:
Also called D.E. A white powder
composed of fossilized skeletons of unicellular organisms called
diatoms. The skeletons are porous and have microscopic spaces. The
powder is added through the skimmer with the pump on and deposits
itself on a grid. The powder then becomes the filter medium.
DICHLOR:
The common name for Sodium Dichloro Isocyanuric Acid. A quick
dissolving chlorine compound made up of chlorine and cyanuric acid
(stabiliser) and has a pH of 6.9. Shock treatment with dichlor is
not recommended as it may result in overstabilisation and chlorine
lock. If dichlor is used, a monthly check of the cyanuric acid
level is recommended, to prevent overstabilisation and chlorine
lock.
It contains 55% available chlorine.
DIFFUSER:
A porous plate, tube or other
device through which air is forced and divided into minute bubbles
for diffusion in the water. A diffuser can also be an over-drain
on a sand filter. A diffuser is also used on a closed- face
impeller on a pump to concentrate water flow to the centre of the
impeller.
DISINFECT:
To kill all pathogenic (disease-causing)
organisms.
DISINFECTANT:
Chemicals, elements or processes
which destroy vegetative forms of microorganisms and other
contaminants. Examples are chlorine, bromine, ionisers, ozonators
and copper & silver algaecides.
DISSOLVED SOLIDS:
Also called TDS or total dissolved solids - A measure of the total
amount of dissolved matter in water. Examples are calcium,
magnesium, carbonates, becarbonates, solium, chlorides and metals.
High levels can cause corrosion, coloured water or salty taste.
Maximum level is usually 2500 ppm for pools. Maximum level for
spas is 1500 ppm over starting level.
DIVERTER VALVE:
A plumbing fitting used to change the direction or redirect the
flow of water. Some diverter valves are used on pool/spa
combinations to allow the use of the spa and then switch the flow
back to the pool. A brand name diverter valve is called an Ortega
valve, which is sometimes used to describe a diverter valve.
DPD:
Chemically, NN Diethyl-p-Phenylene Diamine Sulfate. An indicator
reagent used to measure free available chlorine (DPD1) and total
chlorine (DPD3), bromine, ozone and other oxidizers in water. Far
superior to OTO. Unlike OTO, DPD testing allows determination of
total and free available chlorine levels, which, through
subtraction, gives us combined levels.
DRAIN:
A plumbing fitting installed on the
suction side of the pump in pools. Also called the main drain, it
is located in the deepest part of the pool. Main drains are
connected to the pump for circulation, filtration and emptying of
the pool.
DRY ACID:
Chemically, sodium bisulfate. A dry
white crystal that produces acid when added to water. It is used
to lower pH and total alkalinity and is safer to handle than
liquid acid (hydrochloric acid/ muriatic acid).
E:
EFFICACY:
The power to produce an effect.
Chlorine's efficacy is affected by many factors, including the sun,
temperature, water balance and the water's chlorine demand.
EFFLUENT:
The water that flows out of a pump,
filter or heater, usually on its way back to the pool or spa.
ELECTROLYSIS:
An electrochemical reaction causing
a black stain normally found around metal fixtures or on the
plaster. It is caused by two dissimilar metals being plumbed
together or from an improper electrical grounding of pool
equipment or lights. Electrolysis also means the decomposition of
water and other inorganic compounds in aqueous solution by means
of electricity. Chlorine generators use this principle to produce
chlorine from salt in the water.
ENZYMES:
Used in commercial swimming pool formulations to break down and
destroy oils in the swimming pool.
F:
FIBREGLASS:
Fine threads of glass which are available in the form of a rope or
a mat. When polyester resins, catalysts and hardeners are applied
to fibreglass, it can be formed or moulded into pools, water tanks,
boats and many other items.
FILL WATER:
The water used in filling or
topping up the swimming pool.
FILTER:
A device that removes un-dissolved
or suspended particles from water by the flow of the water through
a porous substance (a filter medium or element). The three main
types of filters used in pools are sand filters, cartridge filters
and D.E. (diatomaceous earth) filters.
FILTER AID:
A chemical compound added to the
water, filter or skimmer that allows the existing filter to become
more efficient. They are generally flocculants, coagulants and
diatomaceous earth.
FILTER AREA:
The total surface area of the
filter medium that is exposed to the flow of water from the pump,
expressed in square metres.
FILTER CARTRIDGE:
A disposable porous element made of
paper or polyester and is used as the filter medium in cartridge-type
filters.
FILTER CYCLE:
The operating time between cleaning
or backwashing cycles of a filter. Also the amount of time the
filter has water flowing through it each day expressed in hours.
FILTER ELEMENT:
A device inside the filter designed
to trap suspended solids as water flows through it from the pool.
FILTER MEDIUM:
The material used in the filter to
trap suspended dirt particles as the water flows through it. It is
the polyester or paper in a cartridge filter element, the sand in
a sand filter and the diatomaceous earth in a D.E. filter.
FILTER POWDER:
A common name for diatomaceous
earth (D.E.), the filter medium in a diatomaceous earth filter.
FILTER ROCK:
Graded, rounded rock and/or gravel
used to support the sand in sand filters.
FILTER SAND:
Sand made up of hard and sharp
silica or quartz (or similar), which have been graded for size and
uniformity, and is used as the filter medium in sand filters.
The most
common grade used is No. 20 in sand filters.
Nowadays it can also refer to clinoptilolite, the zeolite that is
used as an alternative to quartz as the filter medium in sand
filters.
FILTRATION RATE:
The speed at which the water is
travelling through the filter. It is expressed in litres per
minute per square metre of filter area or in kilolitres per hour
per square metre.
FLOC:
See Flocculation.
FLOCCULANT:
Also called a Flocculating Agent.
Virtually the same as a coagulant, it is a chemical substance (such
as alum) that is used to clump suspended particles or algae into a
heavy mass, which can be caught by the filter or sinks to the
bottom of the pool for vacuuming.
FLOCCULATION:
The combination, clumping or
coagulation of suspended particles so that they form small clumps
or "lumps" (called floc).
FLOW RATE:
The quantity of water flowing past
a specific point in a specified time (e.g. the number of litres
flowing through the filter in 1 hour).
FOAM:
A froth of bubbles on the surface of the water. Usually comes from
overuse of algaecide but may also be caused by soaps, oils or
other contaminants carried into the water by swimmers. Enzymes may
be used for foam control.
FREE AVAILABLE CHLORINE:
The amount of free chlorine in the
pool water that is available to oxidise, sanitise or disinfect the
water. The level can be measured using a DPD1 test kit. It is also
called residual chlorine or available chlorine.
G:
GATE VALVE:
The type that spins "lefty-loosey;
righty-tighty".
GREEN HAIR:
A condition caused by too much
copper in the pool water. Green hair is not caused by chlorine.
The copper may get into the water by the bad practice of placing
trichlor tabs in the skimmer. This acidic product will cause low-pH
water, which in turn will dissolve metals in the equipment. The
dissolved metal (usually copper) then stains hair, fingernails and,
eventually, pool walls. It can also be caused by keeping the pH
too low or misusing acid.
GUNITE:
A mixture of cement and sand which
is sprayed onto the iron reinforced walls and floor of a hole to
build a pool, hence the name. The gunite surfaces are generally
plastered.
GUTTER:
Also called a Skimmer Gutter. An
overflow channel at the edge of the pool through which floating
debris, oil and other things flow and empty into the balance tank.
Pools with gutters generally do not have skimmers.
H:
HALOGENS:
The chemical elements in Group VIIB
of the Periodic Table of Elements: fluorine, chlorine, bromine and
iodine. Only chlorine and bromine are used as oxidisers,
disinfectants and sanitisers in swimming pools.
HALOGEN UNDERWATER LIGHT:
These underwater light units have a
life expectancy of 3000 hours, that’s 3 times more than the
standard sealed beam underwater light.
HAND SKIMMER:
A net attached to a frame, which is
then attached to a pole and is used to remove large floating
pollutants such as leaves and insects from the water's surface.
HARD WATER:
Water that is high in calcium,
magnesium or other salts, which makes it difficult for soap to
lather. Hard water also has a tendency to form scale. When
rainwater passes the through rocks (e.g. chalk and limestone),
mineral salts such as calcium and magnesium carbonate dissolve
into it. This then continues into the water supply and in turn
into the pool/spa water. The hardness of the water is expressed in
parts per million (p.p.m) and anything over 250 p.p.m is classed
as hard water.
HARDNESS,
calcium:
The
amount of calcium and magnesium dissolved in the water. "Water" or
"total" hardness refers to the total magnesium and calcium
dissolved in the water. Calcium hardness refers to just the
calcium. Measured by a test kit and expressed as ppm. The proper
range is 200 to 400 ppm.
HARDNESS,
total: The amount of calcium, magnesium and other salts dissolved
in the water.
HEAT EXCHANGER:
A device located inside the heater
providing for the transfer of heat from the heat source to the
water.
HEAT PUMP:
The antithesis of the air
conditioner, the heat pump's cooling coil removes heat from the
air while the condenser coil transfers it to water cycling through
it.
HERBICIDE:
A chemical compound used to kill or
control plant or algae growth.
HORSEPOWER:
The work done per unit of time. 1
horsepower equals 33,000 foot-pounds of work per minute or
approximately 746 watts. Motors for pumps are rated in horsepower
HYDROCHLORIC ACID:
(HCL). Also called muriatic acid. A
very strong acid used in pools to lower the pH or total alkalinity.
It can also be used for cleaning an empty pool (acid washing).
Use extreme care in handling.
HYDROGEN:
The lightest chemical element. It
is a component of water and a product of many chemical reactions.
pH is a measure of
positive Hydrogen ions in water.
HYDROGEN ION:
The positively charged nucleus of
hydrogen atom. The relative degree of acid or base of a solution (called
pH) is a measure of hydrogen ions.
HYDROGEN PEROXIDE:
An unstable, colourless, heavy liquid used as a bleach in industry
and as an antiseptic in households. It is used as an oxidizing
agent in pools and spas. May also be used to de- chlorinate pool
or spa water.
HYDROJET:
A fitting in the pool or spa on the
water return line from the equipment that blends or mixes air and
water, creating a high- velocity, turbulent stream of air-enriched
water.
HYDROSTATIC PRESSURE:
A force involving built up ground
water, which creates upward pressure beneath the pool shell.
HYPOBROMOUS ACID:
The most powerful disinfecting form of bromine in water. Sometimes
called the killing form of bromine.
HYPOCHLORITE:
The name given to a family of
chlorine compounds including: calcium hypochlorite, sodium
hypochlorite and lithium hypochlorite. They are used as oxidisers,
disinfectants and sanitisers in pool water. When these compounds
contact water, they release Hypochlorous Acid, the active
sanitizing agent.
HYPOCHLOROUS ACID:
The most powerful disinfecting form
of chlorine in water. Sometimes called the killing form of
chlorine.
I:
INFLUENT:
The water entering the pump, the
filter or other equipment of space. Water going into the pump is
called in influent, while water leaving the pump is called the
effluent.
IMPELLER:
The rotating part of a pump that is
responsible for the movement of water through the pump.
The impeller is shaft driven by an electric motor.
INLET:
A fitting in the pool on the water
return line. Water is pumped back into the pool through the inlet
after filtration .
IONISER:
A water sanitiser that uses
electricity to generate metal ions, usually copper and silver. It
works by passing a current through a set of electrodes. The copper
is an algaecide and algaestat, while the silver is a bactericide.
Ionisers can significantly reduce chlorine consumption. If the ion
levels get too high, problems with staining or discolouration of
the water can occur.
IRON:
Iron is a natural element that can
cause the water to become clear brown or green in colour. It can
also result in staining of the pool surfaces. Iron can be
controlled by the addition of a suitable sequestering or chelating
agent.
ISOCYANURATES:
Also called stabilised chlorine. A
group of chlorine pool sanitisers that contain stabiliser (cyanuric
acid or isocyanuric acid) to protect the chlorine from the UV rays
of the sun. The most common types are dichlor and trichlor. The
granular form is dichlor, while the tablet or stick form is
trichlor (usually used in a chlorine feeder). Stabilised chlorine
should be used with care, to avoid problems such as chlorine lock
that may be caused by overstabilisation.
L:
L.S.I.:
See Langelier Saturation Index
LANGELIER SATURATION INDEX:
Also called Langelier Index or
Saturation Index. This index can be used to determine water
balance according to the levels of pH, Total Alkalinity, Calcium
Hardness and water Temperature. When all the parameters are in
balance, the water will neither be corrosive or scaling.
LATERALS:
Elongated, capped plastic nipples
at the bottom of a sand filter. They are slotted to allow for
water passage while keeping the sand in the filter tank.
LEAF NET:
Also called a Hand Skimmer. A net
attached to a frame which is then attached to a pole and is used
to remove large floating pollutants such as leaves and insects
from the water's surface.
LED UNDERWATER LIGHT:
LED underwater lights are simply another way to provide lighting
underwater. They have an average life expectancy of 100,000 hours
with a maximum power consumption of only 25W for the coloured
version.
LIGHT NICHE:
The area in a pool or spa that
house the underwater light.
LINER:
Also called a vinyl liner. The
vinyl membrane that acts as a container to hold water in one type
of pool construction.
LIQUID ACID:
Also called hydrochloric acid or
muriatic acid. It is used for lowering pH, total alkalinity and
for acid washing.
LIQUID CHLORINE:
Chemically, sodium hypochlorite.
Strictly
speaking liquid chlorine is liquified chlorine gas.
It usually has 12% to 15% available chlorine and has a pH of 13.
It is generally cheap, but difficult and dangerous to handle. It
also loses its potency rapidly.
Good for
regular chlorination and super-chlorination
LITHIUM HYPOCHLORITE:
A dry granular chlorine compound with 35% available chlorine and
has a pH of 10.7 . It dissolves quickly and can be used to super-chlorinate
vinyl-liner pools, painted pools and fibre-glass pools
as well as
spas and hot tubs.
LOW WATER SUCTION:
An influent fitting, typically low
on the wall in the deep end of a vinyl liner pool. A cheaper
alternative to a main drain.
M:
MAGNESIUM HARDNESS:
A measure of the amount of magnesium dissolved in the water. It is
part of total hardness.
. It also
causes scale if levels are too high.
MAIN DRAIN:
This usually refers to the drain
that is located in the deepest part of the pool.
It is not a drain, such as a drain on a kitchen sink. Main drains
do not allow the water to drain to waste but rather connect to the
pump for circulation and filtration.
MAKE-UP WATER:
Also called top up or refill water.
It is the water used to replace water lost to evaporation, splash-out,
leaks and backwashing.
MARBELITE:
Also referred to as Plaster. It is
a mixture of white cement and white marble dust used as an
interior finish over the gunite or shotcrete of a pool. It can be
given a colour or it may be left white.
MARCITE:
See Marbelite.
Originally a brand name for a white plaster finish coat from 1/8th
to 1/2 inch thick
MICRON:
A unit of length equal to 1
millionth of a metre. Microns are used to describe the pore size
of filter media. Sand filters have openings of 25 to 30 microns;
cartridge filters have openings of 8 to 16 microns; and D.E. (diatomaceous
earth) filters have openings of 1 to 5 microns. Zeolite used in
sand filters have openings of 3 to 6 microns. A grain of salt is
between 90 and 110 microns.
Humans, without magnification, can see objects 35 microns or
larger.
MICROORGANISM:
An extremely small, living
breathing creature. The purpose of disinfectants, sanitisers or
oxidisers is to destroy these creatures in the pool water.
MINERAL:
Substances such as Calcium,
Manganese, Magnesium, Nickel, Copper, Silver, Zinc, Iron, Cobalt
or Aluminum. Their presence in high non-chelated concentrations
can lead to stains or scale formation. The measure of water
hardness is dependent on these minerals.
MULTIPORT VALVE:
Also called a 6-way or 6-port valve.
Water from the pump can be diverted for various functions by
turning the valve handle. The water may: 1. be sent to waste, 2.
be used for backwashing, 3. bypass the filter for maximum
circulation, 4. filter normally, 5. be used to rinse the filter,
or 6. the valve may have all its ports closed. The pump must be
off before changing a valve setting. Always rotate the valve
handle in the clockwise direction to prevent excessive o’ring wear.
MURIATIC ACID:
Also called liquid acid or
hydrochloric acid. A very strong acid used in pools to lower the
pH and total alkalinity. It can also be used for cleaning an empty
pool (acid washing).
N:
NEUTRALIZER:
A
chemical used to make chlorine or bromine harmless. Used in test
kits to counteract the bleaching effect of the chlorine or bromine
in order to increase the accuracy of pool water tests. Sold as
chlorine and bromine neutralizer, it is used to destroy excessive
amounts of chlorine or bromine, so the high levels will not affect
swimmers.
NITROGEN:
A gas that causes algae to bloom
and disables chlorine. It is introduced into the water by rain and
by swimmers wastes (perspiration, suntan oil, hair tonics, etc.)
When combined with chlorine, nitrogen creates chloramines, which
do not belong in our pool. Maintaining proper chlorine levels will
prevent nitrogen from becoming a problem. Superchlorination can
destroy nitrogen and nitrogenous compounds.
NON-CHLORINE SHOCK
A term given to a class of chemical
compounds that are used to oxidize or shock the water (destroy
ammonia, nitrogen and swimmer waste). They contain no chlorine or
bromine and do not kill living organisms. Swimmers may re-enter
the water in only 15 minutes after adding a non-chlorine shock.
Q:
QUATERNARY AMMONIUM COMPOUNDS:
Also called Quats or QAC. A type of
algaecide composed of ammonia compounds. They are also effective
algaestats for certain types of algae.
R:
RATE OF FLOW:
The volume of water flowing past a
point within a specified time. Usually expressed as litres per
minute or kilolitres per hour (m3/h).
REAGENTS:
The chemical indicators used in testing various aspects of water
quality. (All the little bottles or tablets in your test kit).
RE-BAR:
Reinforcement bar, used to add strength to a concrete. After
excavation of an in ground pool, a steel cage is formed out of re-bar,
and the gunite shell is shot over and surrounding it.
RECIRCULATE:
This setting bypasses the filter, water coming into the multiport
does a U-turn and heads back towards the pool. Used only when the
filter is broken (at least it's circulating), or when adding
specialty chemicals which specify using this setting.
REDOX POTENTIAL:
The abbreviation for
Reduction-Oxidation Potential. It is a measurement of the
oxidiser's (e.g. chlorine) ability to oxidise contaminants versus
the contaminants' (e.g. algae) ability to reduce the oxidiser. It
is an indication of the level of free available oxidiser in the
water. ORP is generally used with automated dosage systems and can
give a fair idea of the sanitation of the water. It is not a
measure of the total or available chlorine. Sometimes called ORP.
RESIDUAL BROMINE:
The amount of free available
bromine remaining in the water after the bromine demand has been
satisfied.
RESIDUAL CHLORINE:
The amount of free available
chlorine remaining in the water after the chlorine demand has been
satisfied.
RESTRICTED
FLOW:
The term used to describe a condition preventing full flow of
water. Restriction can occur with full skimmer or strainer baskets,
obstructions in the plumbing, dirty filter, undersized plumbing or
equipment , or placing devices like, heaters, cleaners or
fountains in the circulation system. Restriction on the suction
side creates higher vacumn, (or suction) while on the pressure
side creates higher pressure.
RINSE:
After backwashing, it's a good idea to rinse for 15-20 seconds to
remove any residual dirt that may "poof!" back into your pool
after backwashing. Rinse flows through the water in filter
fashion, say, top to bottom, but effluent is sent out the waste
line.
S:
SALT CHLORINATION:
They are actually miniaturized chlorine manufacturing plants: the
same technology is utilized. The devices are plumbed in-line and
work by electrolytically converting salt, in the pool water, into
chlorine as it passes over specially coated titanium electrode
plates. Salt must be added to the pool prior to start up, as
directed. Thereafter, salt need only be added occasionally, to
replace that lost due to splash out, pump outs or backwashing.
The device generates Free Chlorine and destroys odorous and
irritating chloramines, as the water passes through the cell.
Chlorine production is controllable by a setting and the equipment
operates in conjunction with the timer controlling the filter.
Properly used, there is much less sensation of chlorine being
present. The other water analysis parameters must be maintained,
as with any chlorine-maintained pool. It certainly is easy-to-use
and convenient and lends itself to pool automation.
SAND:
The filter medium used by a sand filter. It usually refers to
quartz or silica, but may also refer to zeolites.
The grade
most often specified by filter manufacturers is grade No. 20 with
a particle size of 45 to 55 mm (millimeters).
SAND FILTER:
A filter using sand, or sand and
gravel as the filter medium.
The pump diffuses water over the top of the sand bed, and forces
it through the sand and into the laterals on the bottom.
SANITISE:
To kill all micro organisms,
including bacteria and algae, and to remove unwanted contaminants.
SANITISER:
A chemical agent used to remove
unwanted contaminants, and kills and destroys bacteria and viruses
in the water, keeping it clean and healthy.
SATURATION INDEX:
Usually refers to the Langeller
method of water balance test
SCALE:
The precipitate that forms on
surfaces in contact with water when the calcium hardness, pH or
total alkalinity levels are too high. Scale may appear as grey,
white or dark streaks on the plaster, fibreglass or vinyl. It may
also appear as a hard crust at the waterline
SCUM:
The foreign matter which floats to
the surface of the water and forms a layer or a film. It can also
refer to a residue deposited on the tiles or walls of the pool.
Sources of scum are soap, oil, deodorant, hair spray, suntan
lotions and others.
SEDIMENT:
The solid material that
precipitates out of the water and settles to the floor of the
pool.
SEPTUM:
That portion of the filter element
consisting of cloth, wire screen or other porous material on which
the filter medium or filter aid is deposited. The nylon grid on a
D.E. filter is the septum.
SEQUESTERING AGENT:
Also called Chelating Agent. A
chemical or compound that combines with dissolved metals or
minerals in the water to prevent them from coming out of solution,
thus colouring the water or causing stains.
SEQUESTRANT:
A chemical which holds metals in
solution and helps prevent scaling. See Sequestering Agent.
SHOCK TREAT:
Adding large amounts of an oxidiser
such as chlorine, hydrogen peroxide or potassium peroxymonosulfate
to the water to destroy ammonia and nitrogen compounds,
chloramines and other contaminants. As a noun it loosely describes
the products used in shocking, such as hypochlorites, potassium
permonysulfate or hydrogen peroxide. As a verb it describes the
act of bringing the sanitizer level up so high that breakpoint
chlorination is reached. When breakpoint is reached, a "shock" or
perhaps a "lightning bolt" is a better analogy, is sent through
the water, tearing apart molecules and slashing through cell walls.
When algae is present it may be necessary to increase the
chlorine level from 1-3 p.p.m to 5-10 p.p.m to kill the algae. The
amount of shock required depends on the amount of algae present.
It may be necessary to increase the chlorine level to 30 p.p.m in
some cases. This must be done when no one is in the pool and the
pool should only be used again when the chlorine level has
returned to normal.
SHOTCRETE:
A different type of application of the concrete and sand mix which
is used to "shoot the shell". Gunite is pumped dry and mixed with
water at the gun, whereas shotcrete is pumped wet. Plaster is
applied over the shotcrete. Shotcrete is premixed and pumped wet
to the construction site.
SILT:
Soil particles having diameters
between 0.004 and 0.062 mm (millimetres). Sometimes they may be
too small to be trapped by the circulation system. In those cases,
a clarifier or an alum product may be needed.
SIMAZINE:
A chemical substance used in
swimming pools and spas as an herbicide or algaecide. Mainly used
for killing black algae.
SKIMMER:
A device installed in the wall of a pool that is connected to the
suction line of the pump. The suction pulls in water and floating
contaminants.
SKIMMER BASKET:
A removable basket or strainer
placed in the skimmer, which is designed to trap large solids from
the water before they get to the pump or filter.
SKIMMER GUTTER:
Also called a Gutter. An overflow
channel at the edge of the pool through which floating debris, oil
and other things flow and empty into the compensation tank. Pools
with gutters generally do not have skimmers.
SKIMMER NET:
A net attached to a frame which is
then attached to a pole and is used to remove large floating
pollutants such as leaves and insects from the water's surface.
SKIMMER WEIR:
The small floating door on the side
of the skimmer over which water flows on its way to the skimmer.
The weir prevents debris from floating back into the pool when the
pump is off.
SLURRY:
Water containing a high
concentration of suspended solids. D.E. is usually added to the
filter as a slurry by mixing the D.E. in some water.
SODA ASH:
Chemically, Sodium Carbonate. A
base that is used to raise the pH of acidic (below pH 7.0) water.
SODIUM BICARBONATE:
Also called Baking Soda or Bicarb.
A base that is used to raise Total Alkalinity in pool water with
only a slight effect on the pH. Sodium bicarbonate can only raise
the pH of the water to 8.5, regardless of the amount used. Care
should be taken, however, to avoid adding large quantities at one
time.
SODIUM BISULFATE:
(NaHSO4).Also
called Dry Acid. A granular form of acid used to lower the pH
(by
trickle feeding)or
Total Alkalinity
(by dumping)
of pool water.
2 1/2 lbs. of dry acid are equal to 1 quart of muriatic acid.
SODIUM BROMIDE:
A salt of bromine which is used to raise the bromine levels in a
pool before using bromine tablets.
SODIUM CARBONATE:
(Na2CO3).Also
called Soda Ash. A base that is used to raise the pH of acidic (below
pH 7.0) water.
SODIUM DICHLOR:
A granular, stabilised organic
chlorine compound providing 56% or 62% available chlorine that has
a pH of 6.9. Used for regular chlorination.
Contains an ingredient (cyanuric acid or stabilizer) that prevents
the chlorine from being destroyed by the ultraviolet (UV) rays of
the sun. Recommended for use in vinyl- liner, painted or
fibreglass pools and acrylic or fibreglass spas.
SODIUM HYPOCHLORITE:
Liquid chlorine for use in pools.
It usually provides 12% to 15% available chlorine and has a pH of
13. It is generally cheap, but difficult and dangerous to handle.
Good for regular chlorination and super chlorination. Not
recommended for spas. Does not contain conditioner or stabilizer
to protect it from sunlight, but it is protected if stabilizer or
conditioner is already in the water.
SODIUM MONOPERSULFATE:
Active ingredient and chemical name
of a non-chlorine shock treatment or non-chlorine oxidiser. See
Non-Chlorine Shock.
SODIUM PERSULFATE:
Active ingredient and chemical name of a non-chlorine shock
treatment or non-chlorine oxidizer. Does not kill bacteria or
algae but it will oxidize or destroy ammonia, nitrogen and swimmer
waster. Does not increase chlorine or bromine levels the way that
super chlorination does, so water may be entered in 15 minutes
after addition. It will not reactivate bromine.
SODIUM SESQUICARBONATE
A chemical mixture of equal parts
of soda ash and sodium bicarbonate used to increase pH and total
alkalinity in pool and spa water. It has a pH of 10.1.
SODIUM SULFITE:
A chemical that can be used to
neutralise chlorine or de-chlorinate pool water.
SODIUM TETRABORATE:
New technology that renders algae incapable of processing carbon
dioxide, which they need to live.
SODIUM THIOSULFATE:
(Na2S2O35H2O).A
chemical that can be used to neutralise chlorine or de-chlorinate
pool water.
SOFT WATER:
Water that has a low calcium and/or
magnesium content. Soft water can result in the etching of the
pool's surfaces, and should be increased with calcium chloride.
Water, which has less than 50 p.p.m of hardness is normally
considered to be soft.
Pools and spas should never be filled with soft water from a
softener. Water with less than 100 ppm of hardness should be
increased to a minimum of 150 to 200 ppm using calcium chloride.
SOLAR COVER:
A floating pool cover that
increases the water temperature by absorption and transmission of
solar radiation. It also reduces evaporation and pollution from
the environment.
SOLAR HEATING SYSTEM:
A system that consists of panels
through which the pool water passes to increase its temperature by
using the sun's heat.
STABILISED CHLORINE:
A family of organic chlorine
compounds that contain stabiliser (cyanuric acid or iso-cyanuric
acid) to protect the chlorine from the degrading UV rays in
sunlight. Most common types are dichlor and trichlor. The granular
form is dichlor (which
is fact- dissolving and can be used for regular chlorination or
super chlorination)
and the tablet or stick form (which
is usually used in a chlorine feeder - either the floating type or
in-line erosion type) used for regular chlorination only
is trichlor..
STABILISER:
Also called Cyanuric Acid or Conditioner. A granular chemical
added to the pool water which provides a shield to chlorine for
protection from UV radiation. Too much can result in chlorine lock.
STAIN:
A discolouration or a coloured
deposit on the walls or bottom of a swimming pool. Stains are
usually the result of metals such as iron, copper or manganese in
the water. The stains may be green, grey, brown or black. They may
discolour the water without affecting the clarity. Sometimes a
sequestering agent, chelating agent or commercial stain-remover
may remove them. If that doesn't work, the easiest way to remove
the stains is to drain and acid wash the pool.
The metals get in the water because the pH was too low or someone
has added a low-pH chemical directly into the circulation system.
The low-pH chemical dissolves a small amount of metal from the
equipment. The metals begin to come out of solutions & deposit or
stain the walls & bottom. Stains are sometimes confused with scale.
STAIN INHIBITOR:
Also called a Sequestering or
Chelating Agent. A chemical that will combine with dissolved
metals in the water to prevent the metals from coming out of
solution and so avoiding discolouration of the water or stains.
STRAINER BASKET:
The second line of defence is a
basket at the pump. The holes in this are smaller than those in a
skimmer basket, and prevent the pump impeller from clogging up.
SUCTION SIDE:
The plumbing prior to and carrying
water to the pump. This side is under vacuum pressure.
SUPERCHLORINATION:
The practice of adding an extra
large dose (5 to 10 ppm) of chlorine to the water to destroy
ammonia, nitrogen and swimmer waste, which can build up in the
water. This level of chlorine is required to destroy all of the
combined chlorine in the water, which is called breakpoint
chlorination.
SUSPENDED SOLIDS:
Insoluble solid particles that either float on the surface or are
in suspension in the water causing cloudiness. They may be removed
by filtration, but if the particles are too small a flocculant or
coagulant is necessary to enable the filter to trap them.
T
TDS:
See Total Dissolved Solid
TEST KIT:
A manual or electrical device used to measure specific chemical
residuals, levels or demands in pool water. Kits usually contain
reagents, vials, titrants and colour comparators for the tests.
The most common tests are: pH, free available chlorine, combined
chlorine, total alkalinity, calcium hardness, cyanuric acid and
metals.
TEST STRIPS:
Small plastic strips with pads
attached that have been impregnated with reagents to test pool
water. The strips are dipped into the water and the resulting
colours are compared to a colour scale to determine the values.
TIME CLOCK:
Also called a Timer. An electrical
device that automatically turns the pump or pool cleaner on or off
at predetermined intervals or times.
TITRATION:
A method of testing for total
alkalinity, calcium hardness and acid/base demand by adding a
titrant, drop by drop, until a colour change is observed.
TOP MOUNT SAND FILTER:
A top mount sand filter simply
means that the multiport valve is connected via the top of the
filter.
TOTAL ALKALINITY:
The total amount of alkaline
materials present in the water, usually measured as carbonate
alkalinity. It indicates the water's resistance to change in pH.
Low total alkalinity causes pH bounce and in turn causes
metal
corrosion, plaster etching and eye irritation
High total alkalinity causes the pH to cons
