Chlorine Crisis – What Crisis?

Chlorine is the fundamental disinfectant required for swimming pools. Without a constant residual value of chlorine in the water the swimming pool quickly becomes an ugly unhealthy swamp.

The Crisis of cost.

The cost of chlorine “Tablets and Granules” has more than doubled in price and is set to rise still further. Note we are referring to the cost of “so called chlorine tablets and granules” only.

The cause of this is two factories based in Louisiana which during the hurricane season, now three years ago, caught fire and were burnt down. These factories were the principal manufacturers in North America. At the same time, a huge factory in China that makes billions of tons of cyanuric acid for worldwide distribution, a principal ingredient of both tablets and granules, also burnt down. This has upset the supply and demand chain for the last two seasons and is still causing the same problems this season, resulting in extortional prices and empty shelfs in north America. The effect is now being felt across the EU as well.

The Crisis of Supply.

As is always the case first we experience price rises, then shortages, and then no product at all. This year the summer season has started early with very high temperatures in May, in some cases pool water has already reached 25 – 29c, all the heated pools have been comfortably 30c all through May. This adding to demand, whilst supply is already tight.

A bit of Science – Facts about “so called” Chlorine tablets & Granules.

Measurements in ppm (parts per million)

Chlorine tablets (trichloro) contain 10:6 (chlorine:CYA)

Chlorine granules (Dichloro) contain 10:9 (chlorine:CYA)

CYA recommended quantity (by scientists) 30-50ppm where 50ppm is max any more has no recognised benefits, above 50ppm it has only negative attributes.

Chlorine will be used up to disinfect the pool. Allow 2ppm per day therefore in 40 days 80ppm of chlorine & 48ppm of CYA (using trichloro alone).

The quantity of Chlorine required to keep the water safe and free of algae is 7.5% of CYA. Therefore, the higher the CYA level the higher the chlorine level. The higher the chlorine level the more intolerable and the worse the water quality.

Cause and Effect.

Continued use of either or both of chlorine tablets / granules will cause over stabilisation / chlorine lock. This year it will also be an expensive way of delivering a nasty pool experience.

The effect:

These are the attributes associated with over stabilization due to incorrect use of stabilised chlorine:

  • Red blotchy eyes
  • Irritated itchy skin
  • Blond hair turned green
  • Aggravated breathing amongst asthma and hay fever sufferers
  • Heavily bleached swim wear
  • Horribly smelly skin.
  • Algae growth
  • Cloudy water
  • Damage to pumps
  • Corrosive damage to tiles.
  • Green / blue stains in pool grout.
  • Unhealthy water with not enough protection against disease causing bacteria and virus.

Crisis – What Crisis?

The apparent crisis is that the WRONG product is now expensive and will become a scarce commodity.

But this is not a crisis because it was always the wrong solution.

Delivering the solution to the Crisis.

This is the really easy part. You simply balance the swimming pool water stabiliser to no more than 50ppm, then keep the chlorine level at 7.5~10% of the CYA = 3.75 ~ 5ppm. Then the pool is healthy hygienic, safe and comfortable with none of the negative attributes listed above.

Adding liquid chlorine multiple times a day – nominally 8 times a day in small, controlled values, knowing that to disinfect the pool you should use approx. 2ppm of free chlorine per day, using less will mean the water is not sanitised and healthy!

As the summer builds more heated water, as humans use the pools more frequently, as holiday guests arrive the parameters change. As they change then so do the demands.

Intellichems – accurate planned dispensing all day every day.

Intellichems has been designed and developed specifically to meet disinfectant and basic saturation index demands.

By applying the laws of water chemistry – Intellichems is a programmable system that delivers the precise value of chlorine (sodium hypochlorite – AKA liquid chlorine) in small values throughout the day.

Intellichems also dispenses the pH correction required to balance to CO2 off gassing associated with chlorine activity


The strategy.


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This blog article is technically supported by:

Robert lowery / Orenda Tech / Trouble free pools / Richard Falk AKA chem geek.


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