28/09/2026
🅵 F is for FREE CHLORINE 💧
Ever wondered what Free Chlorine, Combined Chlorine and Total Chlorine actually mean?
They’re not three different types of chlorine you add to your pool - they describe what’s happening to the chlorine in your water.
💧 FREE CHLORINE (FC)
This is the chlorine available to sanitise your pool. It works to kill bacteria, algae and other contaminants.
👉 Think of it as your pool’s active sanitiser.
🧪 COMBINED CHLORINE (CC)
This is chlorine that has already reacted with contaminants such as sweat, oils and other organic matter.
When combined chlorine builds up, it can contribute to that strong “chlorine smell” and may cause eye and skin irritation.
👉 This is the chlorine that needs to be dealt with.
📊 TOTAL CHLORINE (TC)
Total chlorine is simply:
FREE CHLORINE + COMBINED CHLORINE = TOTAL CHLORINE
💦 So how do you get rid of combined chlorine?
This is where an oxy-shock can help.
An oxy-shock treatment helps oxidise the contaminants responsible for combined chlorine, allowing the chlorine in your pool to get back to doing its job effectively.
👉 Free chlorine = your working sanitiser
👉 Combined chlorine = chlorine tied up with contaminants
👉 Oxy-shock = helps remove the contaminants contributing to combined chlorine
A pool can have plenty of chlorine in it and still need attention - it’s about understanding what that chlorine is doing. 🏊♀️
