4, Match pH, free chlorine / bromine, total alkalinity & water hardness to the colour chart. Chlorine is a good sanitizer for hot tubs as it dissolves fast and works well in hard or soft water. 1kg Stabilising Chlorine Granules - Stabilising Chlorine granules are manufactured with a stabilising agent to help prevent the destabilisation and destruction of the chlorine by sunlight and UV rays.
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