 Water Hardness
Tap water may not be ideal pool-water for the
following reasons:
The quality and properties of tap water depend
on the area that you live in. For example, water
in Scotland is very “pure” due to
the ground consisting of predominantly hard, granite
rock. Hard rock does not readily dissolve on contact
with rainwater. So, the water remains relatively
unaffected, only collecting minor material after
it hits the ground.
This is given the term soft water and will have
a slightly low pH value (acidic). If left untreated,
this will lead to corrosion.
In Kent, with the chalky white rock, the rainwater
picks up “impurities” such as calcium
salts that increase the alkalinity of the water.
This hard water can be cloudy and cause limescale
formation.
Total Hardness
The “Total Hardness” (calcium hardness)
of water is a measure of the amount of calcium
and magnesium salts such as the carbonates, bicarbonates,
sulphates and chlorides present. This is usually
expressed in parts per million (ppm)
Water hardness is aided by water evaporation.
If water evaporates, the dissolved minerals in
the water remain behind and thus, the concentration
is increased.
Water hardness is important due to the water’s
“hunger” for calcium. If there is
a lack of calcium (below 200ppm), the water will
seek it out from the pool’s surroundings
and fittings. This causes erosion problems.
An excess of calcium, however, leads to scale
formation (calcium deposits). The ideal calcium
hardness level is between 200 and 300 ppm.
 Printable
Version
|
