No Apparent Chlorine Reading?

It is not uncommon to find a lack of colour when carrying out the test for free chlorine usinga DPD No.1 tablet or test strip, when fully expecting to obtain a reading.

Probable causes
• Too much chlorine
If there are no other indicators such as the presence of algae or cloudy water it is highly likely that there is too much chlorine present.
A high level of chlorine will bleach out the colour reagent in the test tablet or test strip and give a false indication, leading you to believe that there is no chlorine present.
When ‘shock’ dosing a pool, care should be taken in calculating the quantity of chlorine required to achieve the desired residual so as to avoid overchlorinating.
Greater control of ‘shock’ dosing can be achieved by the use of Superchlorinator which is supplied in the form of a 450g pot and will add approximately 7mg/l (ppm) to 50m3 (11,000 gallons).
What you may need:
Chlorine/Bromine Reducer 4kg – To reduce chlorine level


All chemical handling should be carried out within the guidelines laid out on the product label.
*Before adding any chemicals to your pool, ensure nobody is swimming  & keep the circulation running to ensure adequate dispersion of the chemicals.*
We have put together a series of troubleshooting guides to help you identify any potential problems with the quality of your pool or spa water, and how to overcome them should they occur.
Whether you buy your Chemicals from us or not, please feel free to use these guides as you please & print copies off to keep in your plant room for future reference.
Click here to find our Troubleshooting Guides. 



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