Cloudy Pool Water

Cloudiness can be caused by a number of different factors :

  • Lack of chlorine and filtration
  • Shock-dosing before adjusting pH to correct level
  • Heavy bathing loads
  • Adding chemicals without pre-dissolving them
  • Algae blooms
  • Precipitation caused by high pH and calcium levels

If pool is cloudy or hazy, check and adjust pH then shock-dose pool and filter 24 hours.
If pool is still cloudy add 1 litre of Liquid Floc per  45,000L and filter 24 hours.   Turn filter off, allow to settle.  Once pool is clear vacuum pool to waste.

Green Water Pool

  • Shock-dose pool with 2kg HTC Granular Chlorine per 45,000L, add 1 litre Busan algaecide and filter 24 hours.  Then add 1 litre Liquid Floc and filter a further 12 hours.  Turn off.  Allow pool to clear completely then vacuum residue on pool floor to waste.

Black Spot Algae

  • A particularly resistant form of algae usually associated with Marble Plaster Pools. 
  • Shock-dose pool with 2kg HTC Granular Chlorine per 45,000L and add 1 litre Busan algaecide.  Filter 24 hours and brush affected areas with stainless steel wire brush.

“Black Spot”

  • A reaction in Fibreglass Pools which produces a cobalt hydroxide accretion on the fibreglass.  This "Black Spot” is removed by addition of Hydrochloric Acid to water which makes the pool water very acidic and dissolves the Cobalt Hydroxide build up. The build up will re-appear, the time frame depending upon the severity of the problem.
  • Once the “black spots” have disappeared bring the pH back up to 7.0 gradually with additions of pH Increase (Soda Ash).

Eye Irritation

Due to one or a mixture of the following :

  • pH levels too low or too high.  Check and re-adjust. 
  • Chlorine level too high – especially after a shock-dose.
  • Chemical levels out of balance.
  • Swimming in pool water for prolonged period with eyes open.


Handy hints

  • If fine debris returns to pool after backwashing allow filter to stand for 30 minutes before turning back on to filter cycle.  If problem persists get a serviceman to check the filter under-drain which probably has split.

  • Always pre-dissolve HTC Granular Chlorine by adding chemicals to sufficient water and allowing to stand until residue settled.  Never add sediment to pool as these are insoluble and will cause the pool to go cloudy.
  • Chlorine smell is usually due to the presence of chloramines.  Shock-dose with HTC Granular Chlorine to burn these out and remove the odour.
  • Replace filter sand every 3–5 years

OR change to Glass Media for longer life and much finer filtration

  • Rule of thumb minimum times for filtration cycles.  In swimming season 1 hour per 4500L.  In winter halve your summer filter program.
  • If pump won’t prime check that “hair and lint” basket lid and O’ring are secure and not allowing in air.
  • Never allow Tri-Tabs to remain in contact with pool surface.
  • To remove stains on floor and walls of most pool types add Hydrochloric Acid to water – check dosage rates with your pool shop