14 g per m³ raises free chlorine by 1 ppm. For a 40 m³ pool that is around 560 g per ppm.

Do I need to pre-dissolve?

Yes for vinyl pools. For tile or concrete pools you can broadcast across the deep end with circulation running.

When can people swim again?

Once free chlorine drops below 5 ppm; usually 2-4 hours after dosing with circulation on.

How long does a 5 kg pack last?

About 9 weeks of daily 1 ppm top-ups for a 40 m³ pool, longer in cool weather.

Will SDIC raise my pH?

No. SDIC dissolves close to neutral pH; that is its main advantage over cal-hypo and liquid chlorine.

Is it OK for vinyl liners?

Yes, provided you pre-dissolve in a bucket. Never let dry granules sit on the liner.

What is the active ingredient?

Sodium dichloroisocyanurate dihydrate (SDIC) at 56% available chlorine with built-in stabiliser.

How much CYA does it add?

About 6 ppm of cyanuric acid for every 10 ppm of free chlorine dosed.

Why does pH stay neutral?

SDIC dissolves with a near-neutral hydrolysis profile, unlike cal-hypo which is alkaline and TCCA which is acidic.

Chlorine demand will not budge?

You have an algae bloom; shock to 10 ppm with cal-hypo.

Drain and refill; SDIC keeps adding stabiliser with every dose.

SDIC vs TCCA tablets?

Granules dose in seconds for fast top-ups; tablets feed slowly through a skimmer for unattended sanitising.

SDIC is pH-neutral and stabilised; cal-hypo is alkaline and unstabilised. Use SDIC for routine topping, cal-hypo for shocks.

Pool Stabilised Chlorine Granules

Name: Pool Stabilised Chlorine Granules
Brand: ClearSpa
SKU: ps-2
Availability: InStock
Rating: 4.5 (6 reviews)

Stabilised chlorine granules (SDIC) for swimming pools. Dissolve in seconds and add 1 ppm of free chlorine per 14 g per m³ without raising pH. The go-to fast top-up granule for outdoor pools.

Adds 1 ppm of free chlorine per 14 g per m³.
Dissolves fully in 30-60 seconds with no residue.
pH-neutral so balance is preserved after dosing.
Built-in cyanuric acid keeps chlorine UV-stable outdoors.
Suitable for daily top-ups, weekly shocks and post-fill chlorination.