Reagent test kits

Reagent Test Kit

- are among the simplest ways to test the water quality

This type of pool-tester is also sometimes called a Dropper test-kit

Watch a video of how to use a Reagent Test-kitReagent Test-kit, presented by Ken Walker, CEO of MyPoolGuru

Step-by-step instructions for using a Reagent Test-kit

  • Fill each side of the test kit with water from 30-50cm (12-15") below the surface
  • Shake out excess water until the level of the water in the test kit is correct
  • Add the appropriate number of drops of reagent to each side according to the colours i.e., use the red chemical (Phenol Red) on the side of the test kit with the red colours
  • Note: Some reagent test-kits use tablets instead of liquids. Do not touch the tablets with your fingers and ensure that they are fully dissolved before taking a reading
  • AstralPool test kits use 5 drops of reagent per side, other makes may vary so read the instructions
  • Use the caps provided with the test kit to avoid contaminating the sample
  • Shake the liquid and compare the resultant colour against the coloured strips included in the test-kit
  • Make a note of the results and your remedial actions in your Pool Logbook
  • Note: - A reagent Test-kit, like the one above, can be used to measure either Chlorine or Bromine
  • pH should be between 7.2 and 7.6
  • Reduce pH - by adding 500g of dry acid (Sodium Bisulphate) or 1 litre of Hydrochloric Acid (per 50 m³  or 13,000 US Gallons of pool water) daily until the correct level is reached
  • Dissolve dry acid in water in a plastic bucket and add either chemical to the pool near the return jets with the pump running
  • Raise pH - by adding 500g of Sodium Carbonate (soda ash or pH-plus powder) per 50m³ or 13,000 US Gallons of pool water daily until the correct level is reached; apply as for dry acid
  • Raise Chlorine levels - by adding Tricloro tablets or pre-dissolved Trichloro granules/powder to the skimmer with the pump on
  • 1 x j200g Tricloro tablet, when fully dissolved in 50 m³ (13,000 US Gals) of water at pH 7.4, will raise free Chlorine levels by 1.5 ppm


  • Add 2 litres of liquid Chlorine or 2 pounds of Calcium Hypochlorite (per 50m³/ 13,000 US Gals of pool water) every two weeks, at dusk, via the skimmer whilst the pump is running
  • Remove the pool-cover during superchlorination and keep it off until Chlorine levels have returned to 1-3 ppm

Important Safety Warnings

  • Never mix pool chemicals except by adding them to the pool water
  • Keep chemicals away from each other, out of reach of animals and children
  • Chlorine compounds and hydrochloric acid are potentially very dangerous
  • NEVER mix them together in the dry or concentrated state; there is a risk of fire or explosion
  • Wear goggles, gloves and old clothes when handling chemicals
  • Wash your hands immediately after handling chemicals
  • Run the pump for 4 hours after adding chemicals to allow thorough mixing
  • It will be safe to swim after 30 minutes or so, depending on the amount of water that passes through the pump
  • A strong flow will mix the chemicals quickly and more thoroughly
  • Flow can be increased by setting the Rotary/Multi-port Valve to 'Recirculate' for a couple of hours, until the mixing is done
  • Wash your hands immediately after handling pool chemicals

How may times have I mentioned about washing your hands immediately after handling pool chemicals? Lots, that's how many times

That’s because it is so important!

Every year literally thousands of people arrive at the Emergency Departments of hospitals with chemical burns, caused by rubbing chlorine residue into their eyes after handling pool chemicals

Some of these folks lose their sight permanently

Here is some good advicegood advice on what to do in the case of chemical burns from pool chemicals: -


Keep a note of all your maintenance, and everything else you do to your pool, in your Log Book

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Ken Walker - MyPoolGuru©