Help & Advice

You can find in this section technical support guides and information to help you get the best out of your pool or spa. Read our Help & Advice here


Troubleshooting problems in swimming pools and spas. Read our FAQs here

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Beginners guide to swimming pool and spa chemical use

Whether you are using a spa or pool for the first time, or just starting up for a new season, it is worthwhile taking some time out to consider the steps required to enjoy a trouble free bathing experience.
Get it right first time by following this easy step by step guide.

Set up your pool

  • Ensure the surfaces are cleaned and that any cracks, leaks or liner damage are repaired.
  • If your pool is new then it should be commissioned by the installer.
  • For above ground pools and family inflatable/fun pools follow the manufacturers set up instructions

Cleaning your pool

  • Remove all leaves, debris and dirt.
  • Brush the sides and bottom of the pool – take care with membrane liners.
  • Drained concrete pools can be cleaned with specific cleaning agents.

Order the Chemicals you need

If you are a new small pool or spa owner an easy way to start is with a OPC Small Pool Chemical Kit or a Spa Starter Kit. These will give you all the basic chemical treatments and a simple way of testing your water chemistry that will allow you to get started. 

Testing the Water

In order for you to enjoy your pool or spa it is important that you test the water on a regular basis and ensure it is kept in good condition. The testing of the pool / spa water will at first seem daunting, however our test kits are easy to use and will give quick accurate results.Shop Water Testers

The basic tests are

  • pH
  • Alkalinity
  • Sanitiser (Free Chlorine or Bromine)
  • Check the water for clarity, ensure it is clear.
  • Calcium hardness
  • Combined chlorine
  • Copper levels 

Filling your pool

  1. Dose OPC Chlorine Shock Granules or OPC Non Chlorine Shock Granules. It is advisable to dissolve granular swimming pool chemical treatment products in a bucket of water before adding the mixture to your water. This avoids neat swimming pool chemicals settling onto pool surfaces and is particularly important with plastic liners, as concentrated chemicals will adversely affect the liner surface .
  2. It often helps to stir the water with a pool brush while the pumps are off to ensure an even distribution.
  3. Chemical usage should always be kept to a minimum to assist in maintaining the water balance.
  4. Do not back wash the filter for at least 24 hours to allow the product to disperse. Consult the filter manual to ensure correct operation of the valve assembly.
  5. When full, allow the filtration system to carry out its daily routine.
  6. Test the water and refer to the Water Balancing section to attain uniformity of pH.


  • Use a water meter when filling the pool for the first time this will give you an accurate water volume (in litres or gallons), useful for calculating chemical dosing.Always record your results and the chemical additions that you make. Keep a note book with the test kit and chemical treatments. Retest the water after the addition of chemicals to ensure you have reached the correct levels. (See Chemical levels 7.3)*
  • If the water is cloudy then it is not safe to swim, Bathers cannot see the bottom and may dive in to shallow water!
  • Bathers in difficulty under the water will not be seen!
  • Cloudy water is an indication that there is a problem with the treatment.

Refer to the swimming pool and spa trouble shooting guide for further information.