I know that my test kit says so many ppm, but what is ppm?

Parts per million (ppm) is a unit of measure used when checking
pool chemicals. The New Jersey Water Association compared
one part per million as: 1 inch in 16 miles or 1 minute in 2 years,
or 1 cent in $10,000.
What are the correct levels I should be looking for in my pool chemicals?

Balanced water has a pH level of 7.4 and 7.6. A total alkalinity range of about 80-120 ppm.
Chlorine in the range of 1.0-3.0ppm.
If your pH, your total alkalinity and your calcium hardness is too low, metal corrosion and
staining of the pool plaster can occur. If your pH, your total alkalinity and your calcium hardness
is too high, scaling, cloudy water and discolored plaster can occur.
You should check your pool chemicals at least once a week, and adjust accordingly. That is why
it is always best to leave your pool chemistry to a professional.

How often should I check my pool chemicals?

As many times as it takes to maintain a consistently balanced water. Once you reach this point
it is advisable to check them every few days. I check mine once weekly and adjust.

Is the effectiveness of chlorine dependant on the pool water pH.

Yes. The ideal pH range for a chlorine treated pool is 7.4 - 7.6. Higher pH decreases chlorine's
killing ability, which is why pools at a higher pH have more difficulty with algae and bacteria.
High pH also promotes scaling. Water with a pH below 7.2 turns aggressive-it can corrode
plaster and metals, cause stains and irritate eyes and skin.

What is conditioner? Why do we need it in our pool and why do we pay extra for it?

Pool conditioner or stabilizer or cyanuric acid, is a sun screening chemical that when used
properly is a very effective control of chlorine. It reduces the loss of chlorine due to evaporation
by the sun. If no conditioner is present in your pool water, your chlorine disappears
very quickly.
You pay extra for it because we do and we pass on that cost to you. Conditioner is applied when
needed year round, but we only charge a small fee for it in the spring. And we only charge for
whatever we add at that time. If more is needed during the year, we do not charge for it.

Is chlorine dangerous?

The following is taken from the July 23 issue of the San Diego Union entitled ‘Pooling the risk,’
by Neal Matthews:
Chlorine is the 17th element on the Periodic Table, chlorine was identified by Sir Humphrey
Davy in 1810. The name derives from the Greek word chloros, meaning “greenish yellow.”

Pool chlorine does not occur naturally, but in combination with dissolved salts is common in
seawater, where it is the fourth most abundant element. As a gas, chlorine is poisonous and
extremely dangerous. Inhaling only 30 parts per million produces immediate chest pain and
vomiting. 50 ppm causes lung injury. A few deep breaths at 1,000 ppm causes death.

Chlorine’s toxicity makes it an excellent liquid disinfectant, killing bacteria and clarifying water.
The chlorine level common in U.S. public pools is 3ppm.

My neighbor’s pool service company uses mostly dry chemicals. Apart from the obvious,
what are the differences between dry and liquid chemicals?

Nearly every pool chemical comes in both dry and liquid form. Usually dry chemicals are much
more concentrated where liquid chemicals are more diluted. For example; A chlorine tablet is
about 99% active chlorine which also contains conditioner. Liquid chlorine is about 16% active.
Liquid is faster acting and results are immediate. Tablets are slow acting as they take much
longer to dissolve.

We don’t think that it is a good idea to maintain a pool purely on dry chemicals alone, and
likewise it is not good practice to maintain a pool on liquid chemicals alone. The Pool Doctor
uses all types of liquid and dry chemicals to keep your pool sanitized and chemically balanced
in the fastest and safest way possible. The only form of chlorine that we do not use is chlorine
gas. Although gas is very concentrated and fast acting, we feel that it is dangerous for animals,
plants and children.

After you have applied the chemicals, how long do we have to wait before we can swim?

About one hour if the chemicals are sanitizing agents applied directly to the pool. However, if
they are applied through chlorinating equipment you can swim immediately.
If we ever treat your pool with specialized treatments, or shock your pool, we leave door hangers
if it is unsafe to swim.

What is a chlorinator?

A chlorinator is a unit that is usually installed on your pool equipment that contains chlorine.
There are dry chlorinators that contain chlorine tablets and there are liquid chlorinators that
inject liquid chlorine into the pool - these are used mainly on commercial pools.
The dry chlorinator allows water to pass through the system and the flowing water dissolves the
chlorine tablet, allowing the chlorine to flow into the pool in a diluted form.
This is a much better way of adding chemicals rather than pouring the solution directly into the
pool. To view our chlorinators please visit our

Can we drink our pool water and will it harm our dog?

Pool water is not meant for drinking either by you or your pet. It can make you both sick,
especially just after we adjusted the chemicals.

Why shower before and after swimming?

It is always a good idea to shower before and after you enter your pool or spa.
Before entering the water, a shower washes off most of the body contaminates such as lotions
and perspiration etc. This keeps the water healthier, allowing your filter to work more efficiently.
You would be surprised how much bacteria the human body can introduce to the water, even
though we feel clean.
After leaving the water, it is a good idea to shower again, so as to wash off all the chemicals that
would normally dry on your body, especially your hair. Chlorine and bromine can damage
normally healthy hair if it is not washed out.

I can see like a fine oil slick on top of my pool water. What is this?

Probably body and sun tan oils, which can clog up the pores on your filter. Always put lotion on
after you swim and shower before entering the water.

I have yellow algae all over my pool, what causes this?

Algae is a plant growing in your pool. It is present because of one or more of the following
  • Chemical imbalance
  • Dirty pool
  • Dirty filter
  • Not filtering long enough
To get rid of yellow algae, clean your pool and filter, brush the algae, balance the chemicals,
increase the filter time and shock the pool. Use algaecide if stains are stubborn.

What is black algae?

Black algae is like a black mushroom with a wax like surface that grows in your pool where dust
or dirt is present. Regular liquid chlorine will not kill it nor will acid. Follow the directions above
for mustard algae then wipe or scrape each black spot with a chlorine tablet. This should get rid
of the problem within a few days.

What’s that yellow stuff floating on my pool and stuck all over my pool tiles?

Springtime is when pollen and other fine particles take to the air. Many people get it confused
with algae. Pollen is very fine and powdery, and for about 4 weeks you notice it on the surface of
the water, where it sticks to the tile line.We cannot do anything about this until it disappears.
Pollen is harmless so you can still swim if you so wish. Your filter will take most of
the particles out of the water.

What’ is the best chlorine alternative?

Most people who are sensitive to chlorine use bromine. Bromine tends to give the water a
green tint and is not as effective as chlorine as a sanitizer.

There are many products on the market which promise the world, like ozonators, lectronators
and other expensive contraptions, but very few are as effective as chlorine.

One of the few natural alternatives that we recommend are mineral purification systems such
Nature 2 and Pool RX. Both systems use natural minerals in the form of a cartridge that fits
in your system, which eliminates the excess bacteria in filtered water. Cartridges on both
systems last from 4 to 6 months and turn clear water into Avian like spring water. Chlorine still
has to be used, but on a lower scale.
If you are interested in any of these systems, or need further information please
e-mail me with
your request. Our prices are competitive and we offer installation within our service areas.
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