Cloudy Water

What is Cloudy Water?

Water containing fine particles that reflect back the light.

The particles are held in suspension by static electric charges which repel one another. The particles are from 0.5 to 5.0 Micrometers in diameter and are too small to be filtered out by a sand or cartridge filter. A Diatomaceous Earth (D.E.) filter will filter fine enough to remove these particles so a D.E. filtered pool rarely has a cloudy water problem.

Particles that cause cloudy water can be from any number of sources such as Algae, Suntan Lotion, Body Fats, Skin Proteins, Sand, Pollen, Earth, Granular Calcium Hypochlorite and Calcium Carbonate.

What Causes Cloudy Water?

  • High pH: Which causes Calcium Carbonate to come out of solution. The pool takes on a milky appearance.
  • Algae. The start of an Algae infestation. In the early stages the pool may just seem hazy but after a day or two the familiar green colour develops
  • Heavy Bather Load. Which in reality is a mixture of suntan lotion, body fats and skin proteins. All these products react with Chlorine to form insoluble compounds which have to be filtered out. Swimmers add significantly to the cloudiness of pool water. We have all seen how a pool that is crystal clear in the morning will be quite hazy at the end of a days swimming.
  • Insufficient filtration time. Pool filtration systems are sized so as to give a complete pool water turnover in eight hours. It follows that all pools need eight hours filtration every day. It is also possible that filtration equipment too small for the pool has been fitted.
  • When the backyard washes into the pool after a thunderstorm. A regular occurrence for some pool owners and a nightmare for others. When rain water washes over garden beds before emptying into the pool it collects a variety of chemicals which effect the pool including detergents, nitrates, phosphates, metals that can stain, Algae spores, as well as assorted cigarette ends, plastic bags and doggie do doos.

How Cloudy is the Water?

In order to recommend the correct treatment it is essential to find out how cloudy the water is.

As a guide use:

  • Hazy. Pool Water has lost its sparkle.
    • Cloudy. Pool Water no longer clear but pool owner is able to see the bottom in the shallow end.
    • Very Cloudy. Unable to see the bottom of the pool

Chemical Treatment.

A Clarifier is a chemical that coagulates fine particles together which then are filtered out. A Flocculant is a chemical that coagulates fine particles together, which when the pump is turned off, fall to the floor of the pool under gravity and are then vacuumed to filter or to waste.

Before chemical treatment it should be noted that dose rates for Clarifiers and flocculants are important. Overdosing of chemicals will not improve the clarity faster nor will twice the dose clear twice as much cloudiness.

In fact overdosing can make matters worse, especially with products containing Alum.

Clarifiers and Flocculants work by neutralising the positive electric charge on the particles which then clump together and are either filtered out or fall to the floor. Too much Clarifier or Flocculant can reverse the charge on the particles making it much harder to filter them out.

All Clarifiers and flocculants work in 24 hours or less. Lo-Chlor Pura Blue and Ultra Kleer Plus 4 in 1 work in under 4 hours, so if a pool owner wants to use more, it is better to use single measured doses every day rather than a large dose once only.

It takes about 2 hours to thoroughly mix in a dose of Clarifier or Flocculant.

Treatment for Hazy Water:

  • Adjust pH to 7.2 to 7.6.
  • With pump running add a single dose of either:

Lo-Chlor Pura Blue Clarifier

Lo-Chlor Ultra Kleer 2 in 1 or  Lo-Chlor Ultra Kleer Plus 4 in 1

  • Continue filtering until clear, usually less than 12 hours.
  • Note: Lo-Chlor Ultra Kleer 4 in 1 is recommended for haziness caused by high bathing load.

Treatment for Cloudy Water:

  • Adjust pH to 7.2 to 7.6.
  • With pump running…
  • For a cartridge filter that does not have a waste line add a clarifier dose of Lo-Chlor Ultra Kleer 2 in 1 and filter for 12 hours or until clear. The actual time will depend on how good the cartridge is, if it is very old and has been cleaned a lot, the time will be increased.
  • For a sand filter add a clarifier dose of Lo-Chlor Ultra Kleer 2 in 1 or Ultra Kleer Plus 4 in 1 and filter for 8 hours and turn off the pump. Allow any particles not filtered out to settle to the bottom overnight. Vacuum any residue to filter or to waste.
  • Note: If the cloudiness was caused by the start of an Algae infestation it will be necessary to perform an Algae treatment otherwise the cloudiness will return in 24 hours and get worse.

Very Cloudy Water.

  • Top up the pool to the coping. (vacuuming to waste loses 75 to 100 cm of water)
  • Adjust pH to 7.8 (this gives the most compact floc that will not fluff up as the pool vacuum is pushed through it.)
  • With filter on recirculate (or if a cartridge filter, take out the cartridge)
  • Add the required dose of Lo-Chlor Maxi Floc Plus. (Maxi Floc is Alum in liquid form which has the advantage of being pH neutral. If using granular Alum also add 2 Kg of Soda Ash or 4 Kg of Buffer either through the skimmer on recirculate or dissolved in several buckets of pool water.)
  • After 2 hours turn off the pump.
  • Leave stand overnight.
  • In the morning vacuum to waste. If after vacuuming the water is still cloudy leave the pump off a further 24 hours and vacuum to waste the next day.
  • Note 1…
    Alum or Pool Floc must never be filtered through a D.E. or Cartridge filter. The Alum will immediately clog the pores of the filter and probably mean a new D.E. septum or Cartridge.
  • Note 2…
    If the pool has not settled overnight there is something wrong. First check the pH is between 7 and 8.2. If not adjust using Soda Ash dissolved in a watering can of pool water and broadcast over the pool.
    If pH is OK add 20 Litres of Liquid Chlorine by watering can.
    In both cases leave the pump off overnight and vacuum to waste in the morning.
  • Note 3…
    If the pool was cloudy with Algae, the floc treatment must be followed by an Algae treatment.