Stabilised Shock Chlorine Granules for Pools – 1 kg
iopool Stabilised Shock Chlorine 1 kg is a fast-dissolving granular chlorine treatment designed to raise chlorine levels in swimming pool water when additional disinfection is needed.
It can be used for pool start-up, green water treatment or to correct a low chlorine level. Based on sodium troclosene dihydrate, the product contains 54% available chlorine (± 2%), according to its label.
The 1 kg container provides a practical quantity for occasional treatment, with specific dosing instructions for different water conditions.
What is shock chlorine used for?
Shock chlorine is used to rapidly increase the chlorine level in pool water when disinfection needs to be reinforced.
Unlike slow-release chlorine, which is intended for routine maintenance, shock chlorine is designed for situations requiring a faster increase in chlorine concentration.
The granules dissolve quickly and act against microorganisms, including algae and bacteria.
This product contains stabilised chlorine, formulated to help protect chlorine against degradation by ultraviolet light.
When should you use shock chlorine?
This product is intended for several treatment situations:
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Pool start-up: to carry out the initial chlorine treatment when bringing the pool into use.
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Green pool water: to address algae-related water problems.
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Low chlorine readings: to increase the chlorine level when testing indicates that a correction is needed.
Shock chlorine should not be added according to an arbitrary fixed schedule. The need for treatment depends on water test results, pool conditions and the relevant usage instructions.
How much shock chlorine should you add per 10 m³?
The label provides three separate dosing instructions for 10 m³ of swimming pool water.
| Treatment situation | Label dosage |
|---|---|
| Pool start-up | 150 g per 10 m³ |
| Green water | 80 g per 10 m³ |
| Low chlorine level | 9 g per 10 m³ to increase chlorine by 0.5 ppm |
Before treatment, check that the water pH is between 7.2 and 7.4, as specified on the label.
These doses apply to different situations and must not be used interchangeably. Always select the appropriate treatment and follow the manufacturer's instructions for your pool.
For manual testing of free chlorine, pH and stabiliser (CYA), consider the iopool 6-in-1 pool test strips.
How to use shock chlorine granules
Follow the application instructions printed on the product label.
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Test the water: check the pH and chlorine level. Measure stabiliser when required.
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Check the pH: make sure it is between 7.2 and 7.4 before treatment.
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Select the correct dose: identify the treatment situation and follow the instructions applicable to your pool volume.
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Switch on filtration: ensure the filtration system is operating and the skimmer contains no other chemical treatment.
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Add the granules directly to the skimmer: this is the application method stated on this product's label. Keep filtration running.
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Test the water after treatment: verify water parameters before allowing swimming to resume.
Never combine this product with other pool chemicals.
Product specifications
| Specification | Details |
|---|---|
| Product type | Stabilised shock chlorine |
| Form | Fast-dissolving granules |
| Pack size | 1 kg |
| Active substance | Sodium troclosene dihydrate |
| CAS number | 51580-86-0 |
| Available chlorine | 54% (± 2%) |
| Main purpose | Rapid pool water disinfection |
| Intended application | Swimming pools |
If you need a different pack size, you can also view the iopool 5 kg shock chlorine product. Always check the specific label and instructions for the product being purchased.
Safety precautions
Shock chlorine must be handled carefully and in accordance with the product label.
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Wear protective gloves, protective clothing and suitable eye protection.
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Use outdoors or in a well-ventilated area.
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Never mix shock chlorine with other chemicals, particularly acids, as dangerous gases may be released.
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Observe the incompatibilities identified on the label, including bromine and PHMB.
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Store in the original closed container, away from heat and out of children's reach.
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Do not discharge unused product into drains or waterways. Follow the applicable disposal instructions.
Warning: harmful if swallowed, causes serious eye irritation, may cause respiratory irritation and is very toxic to aquatic life with long-lasting effects.
Swimming should only resume after checking that water parameters meet the requirements applicable to your pool. The label does not establish a universal waiting time after treatment.
Use biocidal products safely. Always read the label and product information before use.
Monitor pool water with iopool
The iopool app can help you track pool water conditions and identify when maintenance or treatment may be needed.
With the EcO Start connected pool analyser, you can monitor pH, ORP (oxidation-reduction potential) and water temperature.
ORP indicates the oxidation-reduction potential of the water; it is not a direct measurement of free chlorine concentration.
Manual testing remains useful for checking chlorine and stabiliser levels.
The iopool app provides additional guidance but does not replace the manufacturer's instructions.
Frequently asked questions
Does this shock chlorine contain stabiliser?
Yes. It is a stabilised chlorine product. Monitoring cyanuric acid (CYA) levels is particularly relevant when using stabilised chlorine repeatedly.
Should I dissolve these granules in a bucket first?
No. The label for this specific product instructs users to add the granules directly into the skimmer while filtration is running. Make sure no other chemicals are present in the skimmer.
Is shock chlorine the same as slow-release chlorine?
No. Shock chlorine is intended to raise chlorine levels rapidly during occasional treatment. Slow-release chlorine is intended for ongoing pool maintenance.
Can I use this product in a hot tub or spa?
The supplied product documentation refers to swimming pool treatment. Spa compatibility has not been confirmed for this reference and must be checked separately.
How soon can I swim after shock chlorination?
Swimming can resume only once chlorine and pH readings meet the appropriate conditions for your pool. Do not rely on a universal one-hour or two-hour waiting period.