In a nutshell, keep
the water balanced, keep the sanitizer level in the proper range,
keep the pool clean, and run the pump all the time. It is as
simple as that. Now you know the secret to crystal clear,
sparkling pool water.
Water
Balance: There are several factors that create what pool people
call balanced water. Total Alkalinity, Calcium Hardness,
Stabilizer, and pH. When all of these are within the
recommended ranges we call the water balanced. Let's look at
them individually.
The pH of
your pool water should be within a range of 7.2 to 7.6. If
the pH is lower than 7.2 the pool water is acidic and if left in
that condition for long periods of time it can corrode the metal in
and around the pool. It is especially hard on the copper
exchanger in you pool heater. Acidic water will use up the
chlorine in the pool, reducing its ability to sanitize. If
the pH gets above 7.6 it can cause cloudy water, scaling around the
water line and in the plumbing; chlorine becomes lazy and doesn't
do its job as well, and algae grows better in a high pH
environment.
The secret to keeping the pH
within the recommended levels is Total Alkalinity
which is sodium bicarbinate, which is baking soda. (Baking
Soda from the grocery store is a little expensive for pool use, but
if you have a chemical supplier in your area, he probably has it in
50 pound bags for a fraction of what you will pay elsewhere.)
It acts as a buffer for the pH and should be kept between 80
and 120 ppm. The pH will be low one day so you add a
little pH increaser and tomorrow it will be high, so you add a
little decreaser, and tomorrow it is low again, etc. This is
what we call pH bounce. You will never be able to get the pH
to stabilize without the Total Alkalinity in the proper
range. Alkalinity is lost through to dilution due to
backwashing, vacuuming to waste and refilling the pool. I
recommend testing the alkalinity at least once a month.
Swimming pool water
requires 180 to 220 ppm Calcium Hardness,
which is Calcium Chloride and can also be purchased at a chemical
supply store. If your calcium level gets low the water
becomes aggressive and will pull calcium wherever it can find
it. If you pool is concrete or gunnite this process can cause
premature deterioration. If you think you don't need it
because you have a liner pool, think again. Everytime you get
out of the pool you bring a gallon or so of water out with you and
it sits there on your concrete deck, looking for calcium.
Calcium, like alkalinity is lost through dilution. If you use
chlorine as a sanitizer then you probably shock with Calcium
Hypochlorite. Notice the first word there - calcium.
This will help keep your calcium level up. I recommend
testing and replinishing at least once a month.
Sanitizers: The most common pool
sanitizer is chlorine, usually in the form of tablets or
sticks. If
you sanitize your pool with chlorine, you should use a form of
chlorine that has Stabilizer in it. This is
cyanuric acid which is combined with the chlorine during the
manufacturing process. Stabilizer acts as a sunscreen for the
chlorine. The sun can remove up to 5 ppm of chlorine from
your pool water in 4 hours. That makes it difficult to keep a
chlorine level of 1 to 3 ppm in pool water without
stabilizer. You will need to add stabilizer to a fresh filled
pool to bring the level up to between 30 and 50 ppm. The
chlorine tablets you use to sanitize the pool will
usually replenish what you loose to dilution during the
season. but check it every year when you open the pool. If
you have a salt chlorine generator, you will need to add stabilizer
to the water to protect the unstabilized chlorine manufactured by
the system.
Biguinide is a non-chlorine
sanitizer. It is liquid and the biguinide level should be
kept between 30 and 50 ppm. Biguinides are not affected by
sunlight and you will not need stabilizer.
Water
Testing: Test the water balancing chemicals at least
once a month and test you sanitizer at least weekly. Use test
strips or the drops. You have a pretty wide range on the
balancing chemicals and either is accurate enough to keep you
within the range. You might want to have the water tested at
a pool store occasionally, just to see how well you are
doing.
Run that
Pump: You may be saving money on the electric bill by
only running the pump 8 to 12 hours per
day. Unfortunately, all of that savings will go
into chemicals to deal with your water problems. The pump
pulls water out of the pool and forces it into the filter where it
is cleaned and then sent through the chlorinator where
sanitizer is added and it returns to the pool. When the pump
is off the water isn't being filtered, and sanitizer isn't being
added to replace what is being used by dust, leaves and other
debris falling out of the air. In addition to that, the water
is just sitting. Poor water circulation is the
primary cause of pool water problems.
Water
Circulation: If your pool has a main drain,
keep it open. It pulls water from the bottom of the
pool through the filter and it helps keep the water
moving. If you don't have a main drain, point the
water return inlet at the deep end toward the bottom of the
pool so it will move that water. Othewise point
them slightly down and in the same direction so the water
moves around the pool. It is worth repeating again.
Poor water circulation is the primary cause of pool water
problems.
Cloudy
Water: Poor circulation and filtration are the most common cause of
cloudy water. Water appears cloudy because tiny, microscopic
particles are suspended in it. It is the filter's job to take these
out, but when the pump is off, the water isn't moving through the
filter. At the first sign of cloudy water, increase the pump
running time. Shock will burn out these particles. Follow the
manufacturer's directions. You may also want to add a blue
clarifier to the pool water to aid your filter in catching these
particles. A high pH can cause cloudy water so test the
water. If you are going to have to treat the pool for
algae, your chemicals will be more effective if the water is
balanced. The early stages of an algae bloom can also cause
cloudy water. Feel of the walls and if they are slick, treat
the pool for green algae, fast.
Green
Algae: First determine that what you have really is green algae.
Mustard algae will eventually turn your water green too.
Green algae will usually cause your water to look cloudy a day or
two before it turns green. Green algae will grow on the
pool surfaces and cause them to feel slick. Make sure
the water is balanced and the pH is in the 7.2 to 7.6 range (a
little closer to the low side is better). Double shock the
pool. That would be 1 pound of shock for every 5,000 gallons
of water, or if you use biguinide, 1 gallon of shock per 5,000
gallons of water. Run the pump continuously until the water
clears. Frequently the algae will die and the chlorine
bleaches it out and the water looks milky. A blue clarifier
added to the water will help the filter clear this out. There
are products on the market which will help your filter remove the
phosphates from the water. If you can keep the phosphate level near
zero, algae can't grow in your water. I know people in the
pool industry who don't like to sell this product because when
pools don't get algae, their algaecide chemical sales go
down. That means you are saving money!
Mustard
Algae: Mustard algae is more common in pools with poor
circulation. It usually first appears around the corners
and on the steps. It looks like sand and it scatters
like dust when you brush it. You can vacuum it out and it
will be back tomorrow. First, vacuum the pool with the
multiport valve set to waste or drain. It is so fine it will
usually come right back through the filter if you vacuum on
filter. There are two ways to treat it in pools sanitized
with chlorine. You can use a copper algaecide. Follow
the manufacturer's directions. You will want to follow up
with a metal chelating agent after the algae is dead. This
will keep the copper from leaving stains on the pool's
surfaces. You can also use a sodium bromide product along
with shock, again following the manufacturer's directions.
This is my choice of treatments. Most of the products that
chelate the metals in pool water contain phosphoric acid and add
phosphates to the water, and phosphates are algae food. This
is why I see people treat mustard algae and it is back in a
couple of weeks. Use one of the products on the market
which will help your filter to remove phosphates. If you can
keep the phosphate level near zero, algae can't grow in your
water.
Keep the pool
clean. Empty the baskets regularly, especially
during times when the leaves are falling in the water. A full
basket will slow the circulation through your filter and poor
circulation is what? Right, the primary cause of pool water
problems. Use your automatic pool cleaner and if it has a
bag, empty it often, or manually vacuum the pool. Leaves and
other debris that get into your pool water use up the
sanitizer. Sanitizer has two jobs, keeping the pool sanitary,
and preventing algae growth.
The Water Wizard will be adding tips
to this site from time to time, so check back.
