Maintaining your pool may seem a little complicated at first, but
you will soon find how simple it is. Remember the old saying...
”An ounce of prevention is worth a pound of cure.”*
*1 ounce = 1/16th of a pound = 1 ounce=28.349 grams!
Understanding Water balance
- How do we adjust pH?
- Alkalinity (TA)
- pH and Alkalinity
- Calcium Hardness
Sanitising
- About chlorine
- Total Chlorine vs Free Chlorine
- Effect of Chlorine on pH
Stabiliser
Shock Dosing / super chlorination
Common Problems
- Algae |
Treatment / prevention
- Starver “ the best algae insurance”
- Staining |
Metal Stains
Filtration System
- Pump |
Sand Filter
Backwashing
Winter Maintenance
Salt Water Pools
Understanding Water Balance
pH. This is the measure of acidity or alkalinity of water. It is measured
on a scale ranging from 1 to 14.
A pH of 7.0 is neutral
Above 7.0 the water is alkaline
Below 7.0 the water is acidic
pH should be maintained between 7.2 – 7.6
Incorrect pH can cause eye irritations, cloudy or coloured water, scale
formation and corrosion of metal parts.
How do we adjust pH?
If pH is high – alkaline, we use acid.
If pH is low – acidic, we use an alkali.
Acid is available both in liquid and dry forms. Liquid acid is Hydrochloric
Acid. Dry acid is Sodium Bisulphate. (pH decrease)
Sodium carbonate (pH increase) will raise pH quickly and have little
or no effect on alkalinity. Sodium Bicarbonate (ph buffer) will raise
pH slowly, while lifting alkalinity quite rapidly.
There are several factors that can change pH. These include swimming,
rain, algae and the addition of chemicals.
The best way to counter these changes is to establish a good level of
alkalinity in the pool.
Alkalinity (TA)
This refers to the amount of carbonates and hydroxides dissolved in pool
water. Total Alkalinity is measured in parts per million (ppm).
Alkalinity lets us control the speed and ease with which the pH can change,
therefore the higher the alkalinity, the steadier the pH.
Alkalinity should be maintained at between 120 – 150 ppm
If this is maintained you will have better control over the levels, not
just pH, but also of calcium hardness and chlorine. Maintaining a good
alkalinity is generally the cheapest part of pool chemistry to control
yet it can result in the best short and long term benefits because it
leads to better overall water balance.
The importance of the level of total alkalinity is that it acts as a
buffer to change in pH. That is it reduces the reaction of factors that
effect pool water pH. If the total alkalinity is too low the pH of the
pool will be susceptible to rapid change.
pH and Alkalinity
Because pH and alkalinity are so closely related anything you do to one
will affect the other. To raise alkalinity you use sodium bicarbonate
(pH Buffer) and to lower it you use acid, these are similar to the chemicals
used for pH change. If small quantities of acid are added the pH will
be sharply affected but the alkalinity will not change very much. If large
quantities are used then both the pH and alkalinity will come down sharply.
Too low a pH is likely to bring alkalinity down as well.
Calcium Hardness
Hardness refers to the amount of Calcium and Magnesium salts in the pool
water and is measured in parts per million (ppm)
Calcium hardness should be maintained between 175 – 225 ppm
If the water is too ‘soft’ (calcium hardness level is low)
then it will obtain calcium wherever it can. This can mean that it will
draw calcium from the concrete, marble sheen or even the grout in the
tiles.
If the water is too hard (calcium is too high), it will deposit the calcium
out of solution causing cloudy water in the short term, and white powder
deposits on the floor of the pool. If left for a long period it can cause
blocked pipes and impellors, damaged filters and heaters.
If the calcium hardness level is too high the easiest way to lower it
is to partly empty the pool and top up with fresh water.
Sanitising
Granular, liquid and tablet chlorine, and salt are a direct form of chlorination.
How effective these chlorines are in reducing the amount of algae and
other organic material is proportional to the pH of the water.
About chlorine
Chlorine is an oxidizer; this means that it combines with oxygen to decompose
something. If something oxidisable comes into contact with an “active”
or “free” chlorine it is treated almost instantly
Oxidisable material includes algae, bacteria, urine, leaves and organic
material. Once oxidized they are not only neutralized but also significantly
reduced in size, thus reducing the amount of waste product that needs
to be filtered out of the water, making the filtration system much more
efficient. However chlorine’s most important job is to make the
water hygienic and safe to swim in.
Total Chlorine vs Free Chlorine
When chlorine is added to water it has the ability to change into one
of two products
1) hypochlorous acid…. Free chlorine. This is a very effective sanitiser.
2) Hypochlorite ions……chloramines. These are totally ineffective
at sanitizing pool water, these can give a strong odour.
Effect of Chlorine on pH
When chlorine is added to the pool water it will have an effect on pH.
Liquid chlorine and calcium hypochlorite lift the pH while Trichlor and
Dichlor bring it down. So depending on the type of chlorine you use the
pH will have to be adjusted regularly.
Stabiliser
The most common form of stabiliser used in swimming pools is cynauric
acid. This acts as a sunscreen for the chlorine added to the pool water.
Without the presence of a stabiliser, chlorine will dissipate at a rate
of almost 40% per hour.
Stabiliser should only be used in outdoor pools and be at a level of
30 – 50ppm
Shock Dosing / super chlorination
After periods of fine weather and heavy pool usage there will be a build
up of unwanted chloramines in the water. This is the time to super chlorinate.
Super Chlorination is the addition of twice the normal amount of chlorine
– enough to lift the chlorine levels to approx 3.0ppm, this will
enable the oxidation process to remove any unwanted materials from the
water, and also kill any pathogenic bacteria that have become resilient
to a lower level of chlorine.
Super Chlorination should be done once a week in summer and once a fortnight
in winter.
Shock dosing is the same as super chlorinating but with 3 – 4 times
the amount of chlorine. Enough to raise the chlorine level in the pool
to 10ppm. This is highly effective if the pool has a high chlorine odour
(chloramines) or for algae treatment.
For those with salt water chlorinators simply push your boost button
once a week for super chlorination.
Common Problems
Algae
Algae are plants and require nutrients and moisture to grow. Algae exist
everywhere as microscopic spores. These will not give us any problems
until they are provided with an environment they like, i.e. unbalanced
swimming pool. Once growth starts, one algae spore can turn into 10 million
in under 10 hours.
Treatment / prevention
1) Brush visible algae from walls and surface of pool
2) Lower pH to between 6.8 – 7.0, the acid water will dry and crack
the waxy coating on the algae
3) Add required dose of algaecide. Lo-chlor pool algaecide should be added
at a rate of 500ml per 10,000L of water and will remain in the water as
a stabilised copper molecule for up to 3 months.
Starver “ the best algae insurance”
Lo-chlor Starver is a revolutionary product that removes phosphates from
pool water. Phosphates can enter the water from any number of sources
and are essentially a fertilizer, providing all the nutrients algae require
for rapid growth. Starver binds these tiny molecules together enabling
them to be effectively removed from the pool water.
0 phosphates = 0 algae = 0 hassles
If algae are present in the water, you can guarantee that there are also
phosphates. By removing the phosphates from the water you are taking away
the algae food supply, conjunctive use of an algaecide will provide an
inhospitable environment for algae to grow.
Staining
Staining can be broken down into 2 common types, organic and metallic.
Organic stains Leaf and vegetation staining is usually easy to spot and
removal is dependant on how long it has been there. Usually a brown stain
in small spots on the pool surface. Recent staining can be removed by
super-chlorination or shock dosing. More severe staining may require a
lowering of the pH followed by a shock dose.
Metal Stains
These are caused by concentrations of trace elements entering the water
through a variety of sources and can be treated using Lo-Chlor stain removal
products.
1) Identify the stain; most stain removal products are stain specific.
2) Lower chlorine to 0 and pH to aprox 6.8
3) Add appropriate lo-Chlor stain removal product.
4) Add required dose of Lo-Chlor metal solution.
5) Add Mira-clear cube for added protection from reoccurrence
Metal solution acts as a sequestreant. Once the stain has been removed
from the surface of the pool it is important to ensure that it does not
return. Metals removed from the surface will remain in solution until
they drop out again. By using the metal solution these molecules are bound
together so they are large enough to be removed through filtration.
Filtration System
Your filtration system has been specifically selected for your swimming
pool. The high performance equipment has been selected to give you years
of trouble free performance.
Pump
Please visually inspect the leaf basket inside the pump and ensure that
it does not become clogged with leaves.
Sand Filter
Your sand filter removes organic material from your water and will provide
filtration to 3 microns by trapping this material in a bed of sand.
Backwashing the filter on a regular (fortnightly) basis will ensure that
your pool water will remain clean and clear.
Your filtration system should be run for 8 – 10 hours per day over
the summer months and for 1 – 2 hours per day over the winter. This
will help keep your water sanitized and clean.
You can run it less unless the water starts to look dirty, then simply
increase it slightly. By experimenting with run times we can do our bit
for energy savings.
Backwashing
Your sand filter will require regular backwashing, this should be done
at least once a fortnight or more depending on bather load. The filter
must be backwashed when the pressure gauge indicates 30 – 40 kPa
higher than at normal start up pressure. Backwashing will remove trapped
organic matter from the filter and help keep your water clean and clear.
Please follow the steps below.
1) Turn pump OFF
2) Move valve handle to BACKWASH position
3) Turn pump ON and run for at least 5 minutes
4) Turn pump OFF
5) Move valve to the RINSE position
6) Turn pump ON and run for 2 minutes
7) Turn pump OFF and move valve to FILTER position
8) Run pump on normal filtration cycle
Winter Maintenance
Please follow these simple steps over winter to keep your pool crystal
clean and save start up costs next summer.
Lo-Chlor chemicals have designed a simple, inexpensive program designed
to keep your pool hassle free and looking good during the cold winter
months ahead. Here are some simple steps for you to follow and then you
can look forward to happy times in your pool next season.
Step 1: Backwash your filtration system. Lubricate rubber O-rings with
Lo-chlor Hydra Slip Lubricant, a special compound designed exclusively
for use with swimming pool parts
Step 2: Adjust the pool water pH to between 7.2 and 7.6 and superchlorinate
Step 3: Wait 24 hours and then add Lo-Chlor Winteriser algaecide. A single
treatment with this unique product will last up to 3 months.
Step 4: Add required dose of Lo-Chlor Starver. This unique product removes
phosphates (algae food and nutrients) from the water, ensuring that your
water remains algae free.
Step 5: Chlorinate at 14 day intervals. This is to remove any staining
caused by leaves.
Step 6: Run the filter for at least 1 - 2 hours per day
Salt Water Pools
For swimming pools with salt water chlorinators, sufficient chlorine
should be maintainable with reduced filtration cycles (2 – 4 hours
a day). Follow all the above steps except step 5.