Slow-dissolving bromine tablets for spas 20 g - 1 kg
iopool 20 g bromine tablets provide gradual disinfection for spa water through their slow-dissolving formula. They help control bacteria, viruses and fungi while oxidising organic impurities in the water.
Supplied in a 1 kg tub containing 50 tablets of 20 g each, this treatment is designed for regular spa maintenance where bromine is used as the water disinfectant.
Why choose slow-dissolving bromine tablets?
Bromine is particularly suitable for warm water environments such as hot tubs and spas. It remains effective at elevated water temperatures and retains disinfecting activity under pH conditions where chlorine may become less effective.
The main features of these iopool bromine tablets include:
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Slow dissolution: gradually releases the disinfectant into the water.
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Ongoing water disinfection: acts against bacteria, viruses and fungi.
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Oxidising action: helps break down organic impurities.
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Suitable for heated water: a practical option for regular hot tub maintenance.
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Convenient format: 50 individual 20 g tablets in a 1 kg tub.
These tablets are intended for routine disinfection rather than shock treatment.
When should you use bromine tablets?
Use these tablets to maintain spa water that is already treated with bromine.
As the tablets dissolve inside the brominator, additional tablets can be added according to the remaining product and the actual treatment requirements.
Regular water testing is important. Use a testing method specifically suitable for bromine to check the disinfectant concentration before deciding whether more treatment is required.
For further information, read our guide to checking the ideal bromine level in a hot tub.
How many 20 g bromine tablets should you use?
What is the correct dosage for these bromine tablets?
The instructions depend on the treatment system. With a brominator, the label recommends filling the unit and replenishing the tablets as they dissolve. It also provides a separate instruction for systems without a brominator: 5 tablets per 10 m³ of water, placed in a skimmer.
| Treatment configuration | Instructions on the product label |
|---|---|
| With a brominator | Fill the brominator and replenish tablets as they dissolve |
| Without a brominator | 5 × 20 g tablets per 10 m³ of water in a skimmer |
Important: the quantity of 5 tablets per 10 m³ is not a weekly dosage recommendation and must not be automatically scaled down to a 1 or 2 m³ hot tub.
The replacement frequency depends on tablet dissolution, water conditions and the measured bromine level.
How to use bromine tablets
Follow the product label and the instructions supplied with your water treatment equipment.
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Clean the filter thoroughly before treatment.
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Check and adjust the pH to between 7.0 and 7.4, as specified on the product label.
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Adjust filtration time according to water temperature and the requirements of your installation.
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Place the tablets in a suitable brominator, following the equipment manufacturer's instructions.
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Measure the bromine concentration using an appropriate water test.
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Replenish the tablets gradually as they dissolve, taking the water test results into account.
The label also refers to application through a skimmer where no brominator is used, with the specific quantity indicated above. This method must be suitable for the installation and the product's authorised instructions.
Do not place tablets directly into the spa water. The label does not specify a universal waiting time before bathing. Always check that water conditions are suitable before using your spa.
Product specifications
| Feature | Details |
|---|---|
| Product | iopool bromine tablets |
| Treatment type | Routine water disinfection |
| Form | Slow-dissolving tablets |
| Individual tablet weight | 20 g |
| Total packaging | 1 kg tub |
| Quantity | 50 tablets |
| Active ingredient | Bromochloro-5,5-dimethylimidazolidine-2,4-dione (BCDMH) |
| Active ingredient concentration stated on the label | 985 g/kg |
| CAS number | 32718-18-6 |
| Recommended pH | 7.0–7.4 |
| Biocidal product type | PT2 – Disinfectants and algaecides |
Safety precautions and storage
Danger. Harmful if swallowed. Causes severe skin burns and eye damage. May cause an allergic skin reaction. Very toxic to aquatic life.
Always follow these precautions:
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Wear protective gloves, clothing and eye/face protection.
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Keep away from acids: contact with acids can release toxic gases.
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Never mix concentrated water treatment chemicals directly.
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Keep the container locked away and out of children's reach.
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Store in the original container, protected from light and moisture, at temperatures between 5°C and 25°C.
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Do not reuse the empty container or discharge the product into drains or waterways.
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Dispose of unused product and packaging according to applicable regulations.
In case of skin contact, rinse thoroughly with water. In case of eye contact, rinse cautiously with water for several minutes and immediately contact a poison centre or doctor. If swallowed, rinse the mouth, do not induce vomiting and seek immediate medical assistance.
Read the full product label before handling.
Monitor your spa water with iopool
The iopool app helps you monitor water conditions and manage routine maintenance.
When used with the EcO Start smart water analyser, it provides access to pH, oxidation-reduction potential (ORP) and water temperature measurements.
ORP indicates the water's oxidation-reduction potential; it does not directly measure bromine concentration. A dedicated bromine test is still required.
Frequently asked questions
Are these bromine tablets suitable for hot tubs?
Yes. iopool markets these tablets for regular disinfection of spas and hot tubs using bromine treatment. Use them only with suitable equipment and according to the product instructions.
How often should I add more tablets?
The product label does not specify a universal weekly frequency. Replenishment depends on tablet dissolution, the installation's needs and measured bromine concentration.
Can I use these tablets for shock treatment?
These slow-dissolving tablets are intended for routine disinfection. They are not described as a shock treatment product.
How long will a 1 kg tub last?
One tub contains 50 tablets of 20 g. Its lifespan depends on actual consumption, water volume, temperature and the treatment system. No fixed number of weeks can be guaranteed.
Does EcO Start measure bromine directly?
No. EcO Start measures pH, ORP and water temperature. Bromine concentration requires a separate, suitable water test.
Use biocides safely. Always read the label and product information before use.