SWIMMING POOL CARE MADE EASY
Take care of your pool and it will provide you with enjoyable
swimming year after year. If you follow the basics of proper
chemical treatment and filtration,pool care will be simple and
easy to follow.
This section will guide you through the steps you should take
from pool start-up,to in-season care, to winter protection. It even
covers important tips on safetyaround your pool and contains a
handy trouble-shooting guide.
SIZING YOUR POOL
You must know the amount of water that your pool holds in
order to know how much chemical to use. Here is a simple chart to figure out your pool
volume. All measurements should be taken in feet.
ROUND: Diameter x Diameter x Average Depth x 5.9 = Gallons
RECTANGLE: Length x Width x Average Depth x 7.5 = Gallons
OVAL: Long Dia. x Short Dia. x Average Depth x 5.9 Gallons
For all other pools ask your builder, retailer, or serviceman for help.
There are three basic filter types: diatomaceous earth (DE), sand, and cartridge.
Even though each pool may have its own unique plumbing design, all filter systems will
perform the same job. Pool water is drawn through a skimmer or a drain and pumped
through a filter which removes dirt, algae and visible contaminants that
enter the pool. You must operate the filter system at least eight hours per day in order to
remove wastes effectively.
Remember, by filtering properly you will help avoid contaminant build-up and save on
You can protect your filter system by adding the correct amount of sand or DE and cleaning
your filter regularly with a FILTER CLEANER to remove oils and other organics like lint or
hair that may lodge in your filter. Occasionally you may need to apply a CLARIFIER to help
your filter trap minute particles that may be passing through the system.
Your pool is designed to hold the same water for many years. You filter it and
chemically treat it over and over again. During this period of time the water can drift out of
balance and cause corrosion, scaling or even stains to appear. You can easily prevent these
problems by paying attention to the basics of water balance. A good quality test kit will
measure the key components of water balance--pH, Total Alkalinity, and Acid or Alkali
Demand. Use your kit often until you become familiar with your pool and supplement your
tests by having your professional pool dealer perform detailed tests on occasion to verify
your readings and spot trends that could lead to potential problems.
Measures the acidity or alkalinity of pool water on a scale of "0- 14". Extreme acid is "0"
and extreme alkali is "14". The proper pH range is 7.2-7.8. pH readings greater than 7.8 will
lead to cloudy water and scaling on all pool surfaces, inefficient sanitizing, and swimmer
discomfort. pH readings less than 7.2 will lead to corrosion of metal parts such as heaters
and ladders, wrinkled vinyl liners, etched plaster, and swimmer discomfort. You can easily
maintain proper pH by using pH DECREASER or pH INCREASER when needed according to
Measures the level of certain minerals that help control the pH of your pool water.
The proper range of Total Alkalinity is between 80-150 ppm (parts per million). Low Total
Alkalinity allows the pH to fluctuate or "bounce" in either direction and can make it
difficult for you to keep the pH stable. For that reason another name for Total Alkalinity is
"pH Stabilizer". Raise Total Alkalinity by using TOTAL ALKALINITY "INCREASER" according to
label directions. High Total Alkalinity locks in the pH, but usually at pH levels above 7.8.
This condition needs to be corrected with pH DECREASER or muriatic acid. Vinyl, painted
and fiberglass pools usually require somewhat higher Total Alkalinity levels than plaster
pools and you should consult your professional pool store or serviceman for more details.
Measures the level of calcium and magnesium minerals present in your pool water.
These minerals exist naturally in all water but the levels vary greatly from one part of the
country to another. "Soft water" typically contains 50 ppm Hardness or less while "hard
water" may contain 300 ppm Hardness or more. The proper range for plaster pools is 175-
300 ppm Hardness and for vinyl, painted or fiberglass pools the proper range is 125-250 ppm
Hardness. Pool water low in Hardness causes etching of plaster and corrosion of pool
surfaces. Raise Hardness by adding CALCIUM HARDNESS INCREASER according to label
directions. Pool water high in Hardness causes cloudiness and scaling to occur. Control
these symptoms by using SCALE OR STAIN REMOVER according to label directions or drain a
portion of the water and refill with water low in Hardness to dilute the mineral level.
Is an important concern for pool owners who use well water or for pools that contain
copper plumbing such as heaters. Both conditions can yield trace levels iron, copper or
even manganese that can cause water discoloration and staining. Such discoloration can
appear green, blue, brown or even black in color. This is caused by the reaction between
your sanitizer and the particular trace minerals in your pool water. You can prevent the
problem by having your pool water professionally tested for these minerals when your pool
is being filled or at any time during the season. If staining minerals are present apply SCALE
OR STAIN REMOVER as soon as possible according to label directions. Re-apply the
treatment if necessary and consult with
your professional pool dealer or serviceman for more information.
Refers to "chlorine stabilizer", the final part of pool water balance. This is a chemical
that prevents the ultra-violet rays (UV) of sunlight from prematurely breaking down your
sanitizer level so that it can do it's job sanitizing the pool water. CHLORINE STABILIZER will
reduce sanitizer consumption by up to 50% and need only be added once for the entire life
of the pool water. Apply CHLORINE STABILIZER according to label directions and do not
backwash for at least 24 hours.
Now that your pool water is balanced and stabilized, iris time to sanitize it with
chlorine. There are many types of chlorine and your professional pool dealer or serviceman
will explain them all to you. The most economical and convenient choice is STABILIZED
CHLORINATING TABLETS or STICKS. This type of chlorine is applied
weekly and is not affected by sunlight like HTH or liquid bleach. You can dispense TABLETS
or STICKS by placing them in a chlorinator, a floating feeder, or a skimmer basket. Again,
your dealer or serviceman will guide you to the approach that is best for your pool. The EPA
(Environmental Protection Agency) has determined that you must maintain a level of 1.0-
1.5 ppm of available chlorine at all times to continuously kill bacteria, algae and other
micro-organisms that try to inhabit your pool. By using slow dissolving TABLETS or STICKS
you will be able to give your pool 24 hour protection. During pool start-up you may need
extra doses of chlorine in order to satisfy the initial demand of the water. This demand
could include contaminants such as organics and debris that built up before you started
using chlorine. Use your test kit often to check your chlorine level and adjust your
chlorinator or floater as needed to increase or decrease the flow. A few important factors
affect the amount of TABLETS or STICKS that you will consume. They are: Temperature,
Rainfall and pH. The warmer the pool water, the greater the use of TABLETS or STICKS. In
fact, pool water at 80ø-85øF will require twice the chlorine of pool water at 60-65øF! The
greater the bathing load, the greater the use of TABLETS or STICKS. Heavily used pools
increase the load of contaminants such as perspiration, mucous and tanning lotions, all of
which consumes chlorine. The greater the rainfall, the greater the use of TABLETS or
STICKS. Rain washes airborne contaminants such as pollen and algae spores into the pool
and tends to lower the pH of the water by contributing "acid rain", a chemical reaction
between rain and air pollution. Finally, low pH causes chlorine to be "overactive" and
dissipate too quickly. Proper control of
Total Alkalinity will prevent low pH and save on chemical costs.
If you prefer to sanitize your pool water by hand, STABILIZED CHLORINATING
GRANULES is the proper choice. These granules are rapidly and completely soluble
in all water temperatures and provide the same 24 hour protection that you get from
TABLETS or STICKS.
Various contaminants such as swimmer waste, lotions and oils can resist normal
chlorination and start to build up in the pool water. This build up usually occurs during hot
weather and periods of heavy bathing when your filter is already working overtime. A
weekly SHOCK treatment, when applied according to label directions,
will oxidize or burn-up these contaminants. A SHOCK quickly raises the chlorine level
to overcome the contaminants for a period of 12-24 hours. It is best to apply SHOCK
in early evening so that it can work overnight and be burned down to normal levels
the next day. Be sure to continue to run your filter during this period of time.
Algaecides are excellent treatments to prevent or kill algae growth when used with
chlorine. As a preventative, algaecides act as an insurance policy in your pool, killing algae
spores as they enter the water. Algae spores are constantly entering your pool from rain,
wind and dust storms and they multiply rapidly in sunlight and warm water. Routine
chlorination cannot, at times, cope with the rapid growth of an algae "bloom", the visible
outburst of algae. These algae can appear green, brown, black, mustard or even pink in
color. By the time algae has bloomed there are millions of algae cells in every gallon of
water! Your professional pool dealer or serviceman has a variety of algaecides for all kinds
of algae and will recommend the best choice for either prevention or killing needs
STABILIZED CHLORINATING TABLETS (3" Size)
* Slow dissolving, 89% available chlorine, 7 oz. wrapped tablets,
For use in Floaters, chlorinators, or skimmers.
STABILIZED CHLORINATING TABLETS (1" Size)
* Slow dissolving, 89% available chlorine, 1/2 oz. tablets,
For use in Floaters or chlorinators.
STABILIZED CHLORINATING STICKS (2" Diameter)
* Slow dissolving, 89% available chlorine, 8 oz. sticks,
For use in Floaters, chlorinators, or skimmers.
STABILIZED CHLORINATING GRANULES .
Fast dissolving, 62% available chlorine granules,
100% soluble, For hand feeding.
BROMINATING TABLETS (1" Size) .
Slow dissolving, 61% available bromine, alternative
to chlorine, For use in brominators.
UNSTABILIZED CHLORINATING GRANULES . Fast dissolving,
65% available chlorine granules, contains calcium, For hand Feeding.
STABILIZER * Slow dissolving, 100% active granules, to
prevent sunlight From lowering available chlorine in pool water.
pH INCREASER * Fast dissolving, 100% active, to raise pH.
pH DECREASER . Fast dissolving, 95% active, to lower pH
TOTAL ALKALINITY INCREASER .
Fast dissolving, 100% active Sodium Hydrogen Carbonate,
to raise and stabilize pH.
CALCIUM HARDNESS INCREASER
* Fast dissolving, 100% active, to raise and balance calcium level.
SHOCK TREATMENT . Fast dissolving, 65% available
chlorine granules, to oxidize contaminants that build up during year.
ALGAECIDES . A variety of maximum strength algaecides,
to prevent and kill a broad range oF algae.
Check with your dealer or serviceman for details.
SPECIALTY CHEMICALS . A variety oF specialties For clarifying,
stain and scale control, filter or surface cleaning.
Check with your dealer or serviceman For details.
Sometimes even the most experienced pool managers run into problems that require
special treatments. Here are a number of the most common problems and recommended
Make sure the filter is operating properly and the correct amount of filter media has
been used. Adjust the pH, if necessary, to 7.2-7.8 and SHOCK treat the water.
If the condition does not improve try adding a CLARIFIER or filter aid. Continue
filtering and maintain the required level of chlorine. If your pool water is "old" and
has a high level of dissolved solids (calcium, stabilizer, chlorides and other salts)
you may need to drain a portion of the water and refill with fresh water.
Your dealer or serviceman can test this for you and advise the correct action.
There are many types of algae that can infect pool water. The most common types,
floating or clinging green algae, respond quickly to a SHOCK treatment and
dose of maximum strength ALGAECIDE. Be sure to adjust the pH, if necessary,
to 7.2-7.8 before shocking and brush all pool surfaces to expose algae hiding in cracks or
wrinkles. Apply the algaecide the next day. Pink algae and mustard algae require extra care
because they both tend to re-infect pool water very easily. Treat pink algae in the same
manner as already outlined but, in addition, sanitize all pool parts that come in contact
with the water, such as the vacuum hose and head, by immersing them in the pool during
the shock treatment. Treat mustard algae with a special algaecide designed to combat this
strain. Clinging black algae that tends to appear as dots or nodules can be treated by
applying a slow dissolving granular algaecide directly on the algae and by brushing the
algae vigorously to expose it's roots. In all cases apply the ALGAECIDE directly into the pool
as close to the algae as possible.
Reddish or brownish colored water is usually caused by oxidized iron or manganese.
Treat the pool water with STAIN & SCALE REMOVER to coat the minerals
and prevent the oxidation process. Greenish or bluish colored water is usually
caused by oxidized copper. Treat the condition as above and consult with your dealer or
serviceman for more details. Be sure not to confuse green, slimy water that indicates an
algae infection with the greenish cast associated with copper.
STAINS AND SCALE
Stains can develop when colored water is left unattended or when metals such as coins
are accidentally left in the pool. Scale is a crusty build up on pool floors and walls caused by
excessive calcium levels and high pH. Usually both conditions must occur for scale to form.
Both stains and scale can be controlled by lowering the pH, if necessary, and by using STAIN
AND SCALE REMOVER according to label directions.
Severe conditions, especially in plastered pools, may require an "acid wash", a draining and
cleaning performed by your dealer or serviceman.
CHLORINE: TOO HIGH OR TOO LOW
Inability to hold a chlorine reading usually indicates lack of STABILIZER in the water.
Have your water tested for STABILIZER and add if necessary. Also be sure to check your
floater or chlorinator to insure a supply of chlorine. Low readings could signal an excessive
chlorine demand that is not being met. In this case, a SHOCK treatment would be
appropriate. Finally, your testing chemicals (reagents) may be old and need to be
replenished. Check with your dealer or serviceman for accurate water testing. A high
chlorine reading that won't dissipate gradually may indicate too much chlorine is being
added to the water. Check your floater or chlorinator and make the necessary adjustment.
On occasion chloramines (chlorine reacted with swimmer waste) can develop and cause
the chlorine reading to remain high. In this case, a SHOCK treatment corrects the condition
by breaking up the chloramines.
If you live in a climate that requires winterization of your pool you should follow these
1. Have your water tested professionally and add any necessary balancers at this time.
2. Vacuum the pool thoroughly and clean the filter.
3. If you have minerals, high calcium level, or a new plaster pool add STAIN AND
SCALE CONTROL directly to the water.
4. While the pool is still circulating, SHOCK it according to label
direction and be sure to distribute the SHOCK evenly.
5. Prevent winter algae growth by adding ALGAECIDE the followingday.
6. Lower the water level if desired, plug all lines and drain water
from the equipment to prevent freeze damage.
7. Follow all equipment makers recommendations for winter care.
8. Add pool grade anti-freeze to the lines to prevent freezing.
9. Cover the pool with either a mesh or solid cover and fasten itsecurely.
Consult with your dealer or serviceman for the cover that is best foryour pool
and for more details about winter care.
Your pool will bring years of safe and enjoyable swimming if you follow these simple
1. No running, pushing, or foolish play in or near the pool.
2. No diving in shallow or unmarked pools.
3. Children must be supervised at all times.
4. Safety fencing should be added (check local building codes).
5. Keep a first aid kit and manual, a life ring, and a pole on site at all times. Browser Fixed
Safe handling of chemicals should also be the rule.
1. Chlorine products emit powerful chlorine gas and should never be opened
indoors and when opened, avoid breathing fumes.
2. Label directions for use must be followed at all times.
3. Do not mix chemicals. A violent reaction can occur.
4. Never add water to chemicals.
5. Read all warning statements on product labels.
6. Do not take advise from others or experiment on your own.
7. Store all chemicals in a cool, dry place and keep sealed.
8. Most important of all, KEEP CHEMICALS AWAY FROM CHILDREN.
ALGAECIDES: MANY CURES
Algae are constantly infecting water through airborne contact which is accelerated by
rain and wind. If algae spores are killed off as they enter the water by using repeated
algaestatic or maintenance doses of algaecides, the incidents of alga
bloom are effectively eliminated. This is an "insurance policy" approach compared to the
cost of treating alga bloom.
If algae does bloom (become visible), then the best approach is to adjust the pH= 7.2-
7.8, shock treat the water with 7-10 ppm of available chlorine, brush all surfaces
vigorously, and follow with a killing dose ( 5x maintenance dose) of algaecide.
Continue to filter and backwash, if necessary, during the entire episode.
According to the United States EPA (Environmental Protection Agency) all approved
algaecides prevent and kill most strains of algae. There is no rule or clear-cut order to
determine which algaecide to use, so choosing algaecides is similar to
choosing medicines. Start with your favored choice and proceed from there. If algae
persists, try another choice.
Here are the algaecide choices and their characteristics:
QUAT TYPE : This is the nickname for Quaternary ammonium chloride. It is economical,
long-lasting, non-staining (non-metallic), excellent wetting properties (penetrates
microscopic cracks). Will foam if overdosed. Best used for floating
green, clinging green and pink algae. POLYMER TYPE This is the nickname for an organic
polymer. It is fairly expensive, very long lasting, non-staining, and
non-foaming. Manufacturer data suggests it is more stable in the presence of high chlorine
than "quats." Best used for black (Dark green complex) and pink algae.
COPPER TYPE This is a chelated (controlled) copper solution. It is very economical, very long
lasting, and non foaming. Can cause blue staining or "green" hair. Best used for floating
green and mustard algae. SILVER TYPE . This is a silver colloid (controlled) solution. It is very
expensive, short lived (curative use only), and non
foaming. Can cause brown staining if mis-handled. Best used for black and mustard algae.
All other approved algaecides are dilutions or blends of these four types.
ACID & BASE DEMAND CALCULATIONS
Don't overlook the importance of performing Base Demand Tests if your pH is 6.8 or
lower and Acid Demand Tests if your pH is 8.2 or higher.
Many water samples are being reported with pH-- 6.8 when, in fact, the true pH might
be 5.0-6.5! Taking time to perform the Base Demand Test will take the guess work out of
adjusting the pH. Look at the difference:
pH Reading Amount of Product Needed to Attain pH=7.5
6.8 1.5 lbs. Sodium Carbonate per 10,000 gallons
6.5 4.5 lbs. Sodium Carbonate per 10,000 gallons
6.0 10-12 lbs. Sodium Carbonate per 10,000 gallons
If a pool owner uses 1.5 lbs. of Sodium Carbonate when 5 or 10 lbs. is actually required,
the pH reading will still appear as 6.8.
Rule of thumb: For each drop of Base Demand, use one-third (1/3) lb. of Sodium Carbonate
per 10,000 gallons.
The calculation for Acid Demand reveals a similar pattern with an extra complication
related to the level of Total Alkalinity. This is especially true in hard water areas and with
curing plastered pools. An extra amount of acid may be needed to lower
the both Total Alkalinity and pH.
pH Reading Amount of Dry Acid Needed to Attain pH= 7.5
8.2 1.5 lbs. Dry Acid per 10,000 gallons
8.5 4-5 lbs. Dry Acid per 10,000 gallons
9.0 10-12 lbs. Dry Acid per 10,000 gallons
For those who prefer Muriatic Acid, the conversion factor from Dry Acid to Muriatic
Acid (Hydrochloric Acid) is:
10 lbs. of Dry Acid -- One (1) Gallon of Muriatic Acid
Because of the connection between high pH and high Total Alkalinity the following
information should be considered. The most common technique to reduce Total Alkalinity
is to pour Muriatic Acid in a series of "pockets" in the deep end of a
pool, keeping away from the walls and floor, if possible. Use of Muriatic Acid seems to
reduce Total Alkalinity with less impact on pH than use of Dry Acid.
Rule of thumb: 1 Gallon of Muriatic Acid reduces 60 ppm of Total Alkalinity in 10,000 gallons.
ALGAE: SOME STUBBORN FACTS
Algae, algae, algae... green, black, mustard, and pink. Why do you use algaecides?
When do you dose? Which one? How much? These questions are asked over and over again.
It seems that everyone has their own opinions about algae control
and here are some of the most widely held beliefs:
Algaecides are not necessary because chlorine kills all. This may be true in theory, but
the chlorine level must be kept high at all times (3 ppm or higher) and not permitted to slip.
This can be expensive, irritating to swimmers, will lead to bleached
swimwear and vinyl liners, and is difficult to maintain. Even in high chlorine, some algae
"habitate" or become accustomed to a steady level. In tropical areas, for example, black
algae sets "roots" and seals itself with a tar-like coating that is
unaffected by high levels of chlorine. Mustard algae is another algae that seems to thrive
in chlorinated water.
Algaecides are killers and Algaestats are preventatives. This may be true by definition
but one product does both jobs. The EPA does not recognize the difference between killing
visible algae (Algaecide) and killing invisible algae (Algaestat).
Invisible algae sounds like a contradiction but, in fact, thousands of algae are growing
before they become visible in an algae bloom.
Algae doesn't grow in low pH water. Not true. The most common types of algae such as
"planktonic blue-greens" prefer pH=7.4-9.0. but many types live in pH-- 5.0-7.0. During
periods of hot weather and intense sunlight, photosynthesis is at its peak. As algae grow,
carbon dioxide (food for algae) is withdrawn from the water and the pH drifts upward. It is
most common to see a green pool with a pH-- 8.0.
Algae doesn't grow in cold water. Temperatures have to drop to near freezing before
algae move into a dormant state. Studies in the Arctic Circle indicate that as long as light is
present algae will grow.
Algae can be filtered out of water. This is true for "colonies" of algae that are visible in
the water, but is not true for single ceil algae, for example, that exist as small as 0.5
micron. Diatomaceous earth (DE) filters particles down to 1-3 microns, sand filters particles
down to 15-20 microns, cartridge filters particles down to about 20 microns. Generally, if
you can see it, you can filter it.
CHELATORS & SEQUESTRANTS
The word CHELATE is derived from the Greek word for "claw". In pool and spa chemistry
chelate means a chemical treatment to control or "coat" soluble metal ions and prevent
their oxidation into unwanted colored precipitates. A chelator attaches to a metal ion like
copper or iron and wraps around it like a claw.
There are many types of chelators available in the market. Among the most widely
used is a group of organic acids called "amino polycarboxylic acids". These chemicals are
usually formulated into liquids that quickly attach to copper or iron ions and deactivate
them. Please note that chelators will not react with metals such as finely divided iron
shavings and they react very slowly with metals that are already oxidized or precipitated.
Sequestrants differ from chelators in the way they "coat" or react with mineral ions.
Sequestrants generally have a few active sites on each molecule allowing it to control two
or more metal ions at a time. Because of this, sequestrants are often
more powerful as stain removers and are often sold with specific stain removal directions.
FACTS ABOUT CHELATORS & SEQUESTRANTS
Many chelators and sequestrants have metal ION PREFERENCES called "displacements".
This means that certain metal ions will be coated before others. The usual preference is
iron, then copper, then manganese, then calcium, then magnesium. There are chelators
that favor calcium first.
The EFFECTIVENESS of chelators and sequestrants to coat undesired metal ions depends
on the concentration of the ions to be chelated. For example, it is easier to control 1 ppm of
copper and 1 ppm of iron in soft water (50 ppm of calcium) than
in hard water (350 ppm of calcium). The presence of 350 ppm of calcium in water, for
example, will occupy a large portion of the chelator intended to control the copper and
iron. With this in mind it is advisable to chelate or sequester undesired
metal ions before adding calcium to the water.
The AMOUNT of chelator or sequestrant needed depends on the type of metal ions
present. For example, copper, iron, and
manganese all require about the same amount of chelator whereas calcium requires 50%
more chelator. Reactions to control
metal ions occur within seconds in most cases.
Chelators and sequestrants are PH AND OXIDIZER sensitive. Very low pH, occurring in a
"pocket" of water where acid has been added, can cause loss of chelation. Very high pH,
again a "pocket" effect, can also cause chelation failure and
precipitation of copper or iron. Because most chelators and sequestrants are organic
molecules, they are subject to attack by high levels of oxidizers and "wear off' over time.
This is the reason that most product labels state that continued additions
may be necessary to control metals. With this in mind, it is obvious that shock treatments
should not be performed directly after chelators or sequestrants have been added.
TEMPERATURE and TDS (Total Dissolved Solids) have slight effects on chelation. According to
high temperature and high TDS increase the amount of chelator or sequestrant needed.
METAL CONTROL TECHNIQUES
Soluble metal ions such as copper or iron can exist in water in three different forms. They
1) Unreacted ions. Colorless but ready to react in some manner such as oxidation.
2) Ions already reacted but not yet precipitated. Colored water but not staining.
3) Ions already reacted and precipitated. Clear water but stained surfaces.
There are four different techniques used to control metals depending on their state as
shown above. The control techniques
Chemical chelators or sequestrants pH control. The use of acids or alkalis
Chemical reduction. The use of strong anti-oxidizers Chlorination or oxidation
Chelators and sequestrants chemically coat ions in any of the three states. Effectiveness
varies based on pH, sanitizer level, calcium level, depth of stain and amount of stain.
An acid wash is an extreme example of pH control. Strong acid breaks the bonds of
reacted ions and releases the ions to the unreacted state. Strong alkali such as sodium
carbonate can bond with unreacted ions to form cloudy precipitates which can be easily
filtered or flocked and vacuumed to waste.
Chemical reduction is the opposite of oxidation. It can be used effectively to reverse
reacted iron either in the colored or precipitated states. Reduction brings the iron back to
the unreacted state.
Under certain conditions chlorination or other forms of oxidation such as granular
oxygen compounds or ozonation, are used to produce a cloudy precipitate that is easily
filtered or flocked and vacuumed to waste.
Metal Control Products
Trade Name Example
Chonchelate, Metal Out
Sequest, Stain Off, Spa Demineralizer
Demineralizer Shock II, Sho2X
Hit Hard, More Chlor
CYANURIC ACID TESTING
The Cyanuric Acid (Stabilizer) test is perhaps the most inconsistent water test
performed. Some of the problems of reporting
and reproducing accurate Cyanuric Acid readings are:
1) Temperature of the sample. Try to keep and test the water sample at room
….temperature. The colder the water, the lower the test resuIt.
2) Waiting time before reading. Be consistent at the recommended 30 seconds before
….reading. The shorter the time interval, the lower the test result.
3) Viewing tube cloudiness. Due to a reaction with the Cyanuric reagent, Viewing ,,,,Tubes
become cloudy over a period of a few months. Be sure to rinse the Viewing Tube carefully
after each use. Cloudy tubes are hard to read.
4) Reading higher levels of Cyanuric Acid. The markings of 60, 80, and 100 ppm level ….on
….the Viewing Tube are increasingly close together. Only a fraction of an inch ….separates
….the 60 ppm mark from the 100 ppm mark. Rather than guess in this
….higher range, redo the test by diluting the water sample in half with tap water to ….put
….the test result in a more readable range. Then double your reading to more ….accurately
report the Cyanuric Acid level. Always dilute the water sample and redo ….the test when
over 100 ppm.
An interesting problem with Cyanuric Acid results is that high levels of Cyanuric Acid
notably affects Total Alkalinity. When measuring Total Alkalinity follow this formula:
Total Alkalinity - (Cyanuric Acid level x .30) = True Total Alkalinity
THE FUNGUS (Dark Stains On Liners)
During the past four years a small, but growing number of above ground and in ground
vinyl liner pools have developed dark colored stains that do not respond to normal
chemical treatments such as shock treatments or algaecides. Nor can these
stains be brushed off or scraped off. They appear to be caused by unusual fungus attacks.
In many cases these stains can be bleached out for a time ranging from one week up to two
years (depending on the severity of the stain) using the following
1) Adjust the pH, if necessary, to 7.2-7.8
2) Adjust the Total Alkalinity, if necessary to 100-150 ppm
3) Turn off the filtration system and allow the water to sit.
4) Prior to this step it is very important to note that Trichloro Granules should not
contact the vinyl liner for more than fifteen (15) minutes in order to prevent the ….vinyl
liner from bleaching! Pour 2 lbs. of Nuclo QUICK KILL or Ortex TRICHLORO GRANULAR or
equivalent directly on the affected areas.
5) Spread the granules evenly over the stains and allow direct contact for 7-10 minutes.
Then push the granular pile to the next affected area with a wide pool brush. For stains in
sloped areas, pour granules into a deep-pocket leaf net and ….allow the net to lie on the
affected area for 7-10 minutes. If granules fail through ….the mesh of the leaf net, an
alternative approach is to pour about 1/2 lb. of ….granules into the toe of nylon panty hose.
Nylon hose has a much finer mesh ….construction. In any event, the granules must not
contact the vinyl liner for more ….than fifteen (15) minutes in order to prevent the vinyl
liner from bleaching. Please test this procedure on a small area to determine your vinyl
liner's reactivity. When the stain removal
procedure is complete, start the filtration system and vacuum the remaining granules in
NITRIFICATION & CHLORINE DEMAND
How green is a green pool? When is a normal shock treatment the correct dose
compared to a treatment 3x normal? Or 5x?
These questions test the imagination of anyone who is asked to describe a "green
pool." Maybe one should be asked, "Can you see the shallow end bottom, the hopper, or
even the deep end bottom?"
WHAT IS NITRIFICATION?
If green is really green, it's a good bet that nitrification has taken place. Nitrification is
a micro biological process in which ammonia (NH3)is converted by oxidation into nitrite
(N02) and nitrate (N03). This process is carried out by two bacteria known as Nitrosomonas
. But first, ammonia must be formed. The sources of ammonia are quite plentiful: inorganic
fertilizers, plant protein decay (leaves etc.) and animal protein decay (bugs etc.) Specialized
bacteria decompose the proteins into ammonia in part of an ongoing cycle called the
NITROGEN CYCLE. (see Nitrogen Cycle Chart). Nitrosomonas, in turn, get their energy or
"food" from the newly created ammonia and carbon dioxide, both present in the water.
Once nitrification begins, an accelerating cycle develops. The nitrates, once formed, are
great algae nutrients! And as nitrates accumulate, algae bloom and the water turns
greener and greener. As the Nitrogen Cycle progresses, more and more plant life becomes
available for further bacterial decomposition into more and more ammonia.
WHAT ARE THE EFFECTS?
Nitrification leads to water conditions that range from slight odor to major algae
bloom. These conditions have been observed in both swimming pools and in municipal
waste water treatment systems. The color can
range from a light green tint to an emerald or dark green, or even a black. Water clarity can
range from a hazy deep end to almost solid color at a depth of a few inches.
WHAT CONDITIONS FAVOR NITRIFICATION?
The primary influence is the level of ammonia present. And this level, in turn, depends
on the level of decomposing plant and animal life, and certain fertilizers. A second factor is
pH, especially in the range of pH= 7.5-8.5. A third factor is water temperature in the range
of70-85F. A fourth factor is periods of extended darkness (covered pools) followed by
exposure to sunlight (promotes algae growth). Clearly the "worst case scenario" is a pool
that is carelesslywinterized (not cleaned or vacuumed, little or no sanitizer added),poorly
covered (rips, pin holes, too small etc.), and left covered late into the spring (long
incubation and warming water).
WHAT CAN BE DONE?
Testing for Nitrification is too complicated for a single test such as a nitrate test (being
used by some pool dealers to identify the problem). A nitrate test will only test one part of
the cycle. Research * indicates, for example, that Nitrosomonas bacteria secrete organic
compounds that actually stimulate the growth of other types of bacteria. A test for these
bacteria would be needed too. Data from the Metropolitan Water District of So. Cal. shows
5-10 ppm of chlorine effective in controlling mild nitrification. Severe cases can require 25-
50 ppm of chlorine (5x shock treatment) and repeated treatments in some cases.