Comparing pool care choices
Stabilised or unstabilised chlorine
Stabilised chlorine protects itself from sunlight but leaves something behind. Unstabilised chlorine leaves nothing behind but needs protecting.
Stabilised chlorine products — trichlor tablets and dichlor granules — contain cyanuric acid, which shields chlorine from the sun’s ultraviolet light. In a sunny outdoor pool, that protection matters: without any stabiliser, chlorine can be lost from the water within hours of strong sun. The catch is that cyanuric acid stays in the water, and every dose adds more.
Comparison guides set two pool care choices side by side and say when each suits.
Unstabilised chlorine — liquid sodium hypochlorite and calcium hypochlorite — adds no stabiliser. Used alone outdoors, it disappears quickly in sunlight; used with a moderate, measured stabiliser level added separately, it gives the protection without the build-up. Calcium hypochlorite adds calcium, which matters in already-hard water. Indoor pools usually need no stabiliser at all.
The short version
Stabilised products protect and accumulate
Each dose adds cyanuric acid, which only dilution removes.
Unstabilised products leave no residue of stabiliser
Outdoors they need a separately managed stabiliser level.
Calcium hypochlorite adds hardness
Worth avoiding where calcium is already high.
Choosing for your pool
Outdoor villa pools
A moderate stabiliser level with liquid chlorine gives protection without build-up.
Pools already high in stabiliser
Switching to unstabilised chlorine stops the level rising further.
Indoor or shaded pools
Little UV means little need for stabiliser.
Before choosing a product
Test stabiliser
It decides whether more is helpful or harmful.
Test calcium hardness
Especially before using calcium hypochlorite.
Consider how dosing will happen
Tablets dose themselves; liquid needs a person or a feeder.
Common questions
Is stabiliser bad for the pool?
At moderate levels it is helpful outdoors. At high levels it slows chlorine down.
Can a pool use both types?
Yes, with stabiliser monitored so it does not creep up.
Do salt pools need stabiliser?
Outdoor salt pools usually benefit from a moderate level, added separately.
Related pool care guides
- Chlorine shock or non-chlorine shockA related choice about how the pool is looked after.
- Repairing or replacing a pool pumpA related choice about how the pool is looked after.
- Why a pool smells of chlorineAnother water problem with a related cause.
- Pool water that stings eyes and skinAnother water problem with a related cause.
This guide sits under pool water treatment. Browse all pool care guides. We look after pools at homes and commercial properties across Dubai.
Ask about your pool
Describe the pool and the question. We will answer directly, and say when the honest answer is that nothing needs doing.
Phone
+971 56 181 0106Talk through what the pool is doing and book a time for us to see it.
WhatsApp
Send a messageThe easiest way to send photographs of the pool and plant room.
Next step
Not sure which chlorine to use?
Send a test including stabiliser and hardness. We will suggest the product type that suits your pool.