Pool water pH
The pH is one of the most important factors in pool water balance and it should
be tested and corrected
at least every week. pH is the measure of how acid/ alkaline the swimming pool water
is. A pH of 7.0 is neutral - below 7.0 is acidic, above 7.0 is alkaline.
The pH of our eyes is 7.2 . No wonder that the ideal pH for your pool is
just that - 7.2 , and should be kept within the range of 7.0-7.6 .
What happens when the pool is too acidic?
(pH is low)
- If your swimming pool is Marbelite or plaster, the pool water will begin to dissolve
the surface, creating a roughness which is ideal for pool algae growth.
A similar result occurs in the grouting of tiled swimming pools.
- Metals corrode - and this includes swimming pool equipment, pipe fittings,
pump connections, etc.
- As the swimming pool walls and metal parts corrode, sulphates are formed.
These sulphates are released from the water onto the walls and floor
of the swimming pool causing ugly brown and black stains.
- Chlorine, which is used as a disinfectant in the swimming pool water, is activated
and lost to the atmosphere very quickly. The water is not being sanitised,
and we are throwing away our money by adding chlorine when the pH is
- When we swim, our eyes and nose burn. Our swimwear fades and perishes.
Our skin gets dry and itchy.
What happens when the pool is too alkaline?
(pH is high)
- The calcium in the swimming pool water combines with carbonates and forms scale,
just like in our kettles. This calcification is seen most at the waterline,
where it traps dust and dirt, turning black with time.
- The swimming pool water starts to become cloudy or murky and it loses its sparkle.
- The calcium carbonate has a tendency to plate out on the sand in the
swimming pool filter, effectively turning it into cement. So your sand
filter becomes a cement filter, and loses its ability to trap dirt from the pool water.
- As the pH rises, the power of the chlorine to act on foreign particles
is lost. At a pH of 8.0 the pool can only use 20% of the chlorine you
put in. So 80% of it goes to waste and you would need 5 times as much
chlorine to provide the disinfection you need.
- In alkaline swimming pool water, the swimmers suffer too. Our eyes and nose burn
and our skin gets dry and itchy.
By neglecting to test and correct
the pH of swimming pool water, we not only cause it to become unsightly, but we
also cause ourselves physical discomfort. In addition to this, we insist
on throwing away our hard-earned money on swimming pool chemicals that cannot possibly
be effective in that pool water.
After testing the water, the necessary
chemicals must be added to bring the pH to a level of about 7.2 .