Pool Water Chemistry
Pool water chemistry is the most misunderstood,
yet vital component to overall pool care. Not only does proper water chemistry
protect the swimmers using the pool, but it also protects the swimming pool
itself. Gas heaters, electrical heat-pumps, filters, and even the vinyl-liner
can all suffer severe damage from unbalanced pool water. In order to clear up
some of the confusion surrounding this subject, we have listed some of the more
important water chemistry terms below.
The Chemistry of your pool water is sometimes
the most confusing, yet most important part of your pool care. Proper pool
Chemistry will protect the swimmers, the pool and your pool equipment. Any piece
of pool equipment that is touched by pool water can be damaged if the water
chemistry is not properly balanced. So lets look at some of the issues
regarding pool water chemistry.
Calcium Hardness speaks to how much Calcium ( or other hardeners like
magnesium) is in your pool. Too much Calcium hardness can result can cause
scale, which can make the water cloudy and form residue on pool ladders
and equipment. Calcium Hardness that is too low can lead to corrosion of metal
products in contact with your pool water. The Correct levels for Calcium
Hardness should be between 150 and 300 parts per million.
Chlorine Sanitizers fulfill two functions.
First, they sanitize your pool water, that is killing all the the bacteria that
can accumulate. Secondly, they oxidize your pool water breaking down
ammonia, and other swimmer related by products. They also, in proper levels kill
algae spores before they have a chance to propagate. Levels of sanitizers must
be kept at optimum levels so they can quickly kill or treat whatever
contaminates that can come into your pool waters. The Amount of active chlorine
in your pool water should be in the range of 1.5 and 3.0 parts per million.
TA (or total alkalinity)
TA refers to how much alkaline products there are in your
pool water. Alkaline products protect your pool water from abrupt fluctuations
in pH. TA that is too low can lead to corrosion of metal parts and can damage
the vinyl liners of Above ground pools. You should test often to determine
proper Alkalinity levels, which should be 110 parts per
million for pools that use stabilized chlorine and 80 parts per million for
granular styles of Chlorine.
the symbol for the logarithm of the reciprocal of hydrogen ion concentration
in gram atoms per liter, used to express the acidity or alkalinity of a solution
on a scale of 0 to 14. I t expresses the acidity or alkalinity of water. A
pH reading of 7 is considered neutral lower than 7 and the water becomes
acidic, higher and it becomes alkaline. A pH level of 7.2 to 7.8 is
Stabilizer, usually Cyanuric acid
, is used to prolong the potency of Chlorine
in the water of a swimming pool. Of the two types of chlorines that are
available on the market there are stabilized and non stabilized. Granular
chlorine, tend to be more potent than it's Stabilized cousin and more effecting
at treating algae or cloudy water. If you use non-stabilized chlorine you
should add stabilizer to your pool each spring after balancing the pool water.
Cyanuric Acid levels are optimum in the 40 to 80 parts per million range
Possible Problems derived from off balance
Cloudy or unclear water
Pool water can turn cloudy for a variety of reasons. The most common cause
of cloudy water is either dead algae floating in the pool water or other small
particles floating in the water such as dissolved leaves. The best way to treat
a cloudy pool is chlorine, chlorine, and more chlorine. You should add a large
dose of non-stabilized chlorine (either calcium hypochlorite or sodium
hypochlorite) each day for four to five days straight, keeping your free
chlorine level above 3 ppm at all times and running the pool filter 24 hours a
day. If this does not clear your water, then you can try clarifiers and other
products. But first shock your pool water.
Algae are microscopic plants which can transform your pool water from clear blue
to a swamp in as little as 24 hours. Algae spores are introduced into the pool
through the air, from rain water, and from swimmers walking across the grass and
then jumping into the pool. Algae blooms are common after heavy rain showers and
when the pool water temperature is high. There are many types of algae, the most
common in our area being green algae, mustard algae, and black algae. The most
effective way of preventing algae growth is to maintain a free chlorine level of
at least 1.5 ppm at all times, run the pool filter 24 hours a day, and to add a
dose of algaecide once a week. We have also found that adding Sun Algaecide to
the pool water decreases your chances of suffering from an algae bloom. a Sun
Algaecide acts as an inhibitor against algae growth by lowering algae's ability
to process carbon dioxide in the water making it difficult for an algae spore to
germinate and grow. If you do develop algae, apply the appropriate algaecide,
shock the pool, and brush down the entire pool causing the algae to become
suspended in the pool water. The next day, if anything settles out, vac it out
Tinted Water and Stains
If minerals are present in the pool water, they can cause the pool water to turn
green, brown, yellow, and even purple. The water would look clear but
discolored. It can be very difficult to distinguish between green water caused
by green algae and green water caused by a mineral problem. A telltale sign of a
mineral problem is the discoloring of the pool water shortly after shocking the
pool. If this occurs, you will need to add a mineral sequester to the pool.
Exactly how much is a guess. We have seen cases where one bottle has solved the
problem, and others where multiple bottles were needed. Mineral problems are a
tough nut to crack and the pool industry is just now trying to get a handle on
it. Stains on the vinyl liner are also treated by adding a mineral sequester.
Persistent stains might need to be treated with an "on contact"
product that must be applied directly to the stained area of the pool. If the
stain is on the bottom of the pool, applying the product directly on the stain
can be tricky, but possible.
Due to the acidic nature of our tap water and our rain, we tend to suffer
more from low pH pool water than from high pH pool water. Fortunately,
correcting the pH balance of your pool water is quite simple. All you need to do
is add pH Increaser (also called soda ash and base). But before you add pH
Increaser be sure to get your Total Alkalinity balanced first. Once the Total
Alkalinity is balanced, the pH can be adjusted more accurately.