Free & Total Chlorine

Insta-TEST Free and Total Chlorine Test Strips

Which form of chlorine do you want to measure?
Free chlorine is a measure of how much chlorine is free and available to sanitise.  That is, how much chlorine has not yet reacted with contaminants in the water and is therefore available to kill harmful bacteria and algae.  Free chlorine occurs in two forms: hypochlorous acid and hypochlorite ion.

Combined chlorine is a measure of chloramines.  Chloramines are the by-products of hypochlorous acid's reactions with contaminants.  Once hypochlorous acid has 'combined' with harmful substances in the water (such as sweat in the case of swimming pool water), chloramines are formed.  Think of them as waste products that need to be removed from the water.  There is no way to directly test for combined chlorine, instead we need to test for total chlorine.

Total chlorine is simply a measure of both free chlorine and combined chlorine.  To work out combined chlorine, subtract your free chlorine reading from your total chlorine reading.

total chlorine - free chlorine = combined chlorine

Premium quality packaging!
Insta-TEST Free and Total Chlorine are packaged in LaMotte's patented PopTop bottles, with clever features designed to protect your strips for longer:
•  Molded desiccant liner, eliminating loose desiccant bags.
•  Hinge guarantee for 1000+ openings
•  Airtight & waterproof seal to lock out moisture & light
•  Durable, high density HDPP outer shell

Manufactured by: LaMotte

Safety Data Sheet:  3027 SDS