Works hot, smells less, and needs to be started rather than dosed

The best pool and spa bromine for 2026

Bromine is the alternative halogen, and it exists on this shelf for a specific reason: it holds up at spa temperatures where chlorine does not, and its combined form — bromamine — stays an active disinfectant instead of becoming the chloramine that gives indoor pools their smell. That is the whole case for it, and it is a real one for a heated spa. Three things follow from the chemistry. First, bromine is not stabilised and cannot be: there is no cyanuric acid equivalent, so in an uncovered outdoor pool in full sun it is consumed far faster than chlorine, which is why this shelf is dominated by spa-sized packs. Second, a bromine system works from a bromide bank: the tablets maintain a reservoir of bromide ion in the water that an oxidiser reactivates, so a new spa is started with a sodium bromide dose and then maintained with tablets — a detail that half these listings do not mention and that explains why a first fill can read nothing for days. Third, the tablet weight and the dispenser fit, since 20 g bromine tablets are made for the floating dispensers and in-line feeders that spas use. And the active content, usually stated as available bromine or as BCDMH percentage. We compare active content, tablet or granule format, weight, start-up requirement and dispenser compatibility.

These parts, one figure beside another

1. 

   Cristal Bromtabletten 20 g, 800 g

   Twenty-gram slow-dissolving bromine tablets in an 800 g tin — the smallest pack in this family — stated chlorine-free and dosed through the skimmer or a float.

   Active content

   Not published — as with all seven products in this family

   Tablet or granule format

   Tablet, slow-dissolving

   Tablet weight

   20 g. Pack size 800 g — the smallest in this family, and about 40 tablets

   Start-up requirement

   Not published. No activator is mentioned

   Dispenser compatibility

   Dosed directly into the skimmer or a dosing float, with no additional accessory required, stated. BAuA registration number N-107940

   Amazon reference

   B002UO4HE4 (one reference across 1 Amazon marketplace)

   EAN

   4002369390019

   • The smallest pack on this shelf, which suits a hot tub that would not use a kilogram
   • States the dosing route plainly: skimmer or float, nothing else needed
   • No dose published, like six of the seven products here

   Best for: A hot tub or small pool being run on bromine, where 800 g is a season

   Check price on Amazon
2. 

   Bayrol SpaTime Bromtabletten 20 g

   Twenty-gram bromine tablets for hot tubs in an 800 g pack, and one of two listings here to publish the technical reason for bromine: a high pH tolerance for water that tends to run alkaline.

   Active content

   Not published — as with all seven products in this family

   Tablet or granule format

   Tablet, slow and residue-free dissolving

   Tablet weight

   20 g. Pack size 0.8 kg — joint smallest in this family

   Start-up requirement

   Not published

   Dispenser compatibility

   Not published as a route. High pH tolerance stated as the reason bromine suits hot tubs, where the pH generally tends to higher values

   Amazon reference

   B00CAGF5VQ (one reference across 5 Amazon marketplaces)

   EAN

   4008367393502

   • Publishes the chemical reason for choosing bromine — high pH tolerance in water that runs alkaline
   • Stated to dissolve without residue, which matters in a dosing float with small metering holes
   • No dose published, like six of the seven here

   Best for: A hot tub whose pH drifts upward, where chlorine loses effectiveness as it does so

   Check price on Amazon
3. 

   POOL Total SPA Collection Brom, 50 × 20 g

   The only bromine product in this family to publish a dose: 3 to 4 tablets per 1 000 litres about every two weeks, in a kilogram pack of fifty 20 g tablets.

   Active content

   Not published — as with all seven products in this family

   Tablet or granule format

   Tablet

   Tablet weight

   20 g. Pack size 1 kg, published as 50 tablets — the only tablet count in this family

   Start-up requirement

   Not published

   Dispenser compatibility

   Not published as a route. Dose stated as 3 to 4 tablets per 1 000 litres of water, about every 2 weeks, for continuous disinfection. BAuA registration number N-112125

   Amazon reference

   B0DDY17L59 (one reference across 1 Amazon marketplace)

   EAN

   4251002876001

   • The only bromine listing here to publish a dose and an interval
   • The only one to publish a tablet count — fifty in the kilogram
   • No active bromine content, like all seven products here

   Best for: A hot tub of a known volume, dosed to a published figure on a fortnightly routine

   Check price on Amazon
4. 

   Happy Garden hth SPA Multi-Action 4

   A kilogram of 20 g hth SPA Multi-Action 4 bromine tablets. The title names four actions; the listing carries no bullets at all.

   Active content

   Not published — as with all seven products in this family

   Tablet or granule format

   Tablet

   Tablet weight

   20 g. Pack size 1 kg

   Start-up requirement

   Not published

   Dispenser compatibility

   Not published. Multi-Action 4 in the product name indicates four functions; the listing does not name them

   Amazon reference

   B097BXC76J (one reference across 3 Amazon marketplaces)

   EAN

   3701227216706

   • The only multi-action bromine tablet on this shelf, by its product name
   • hth is an established pool-chemistry brand rather than a marketplace label
   • No bullets whatsoever — the title is the entire listing

   Best for: A hot tub already run on hth products, where the range is the reason

   Check price on Amazon
5. 

   Gre Slow Brom 20 g, 1 kg

   A kilogram of 20 g slow-dissolving bromine tablets from Gre. The title states the format and the speed; the listing carries no bullets.

   Active content

   Not published — as with all seven products in this family

   Tablet or granule format

   Tablet, slow-dissolving — stated in the product name

   Tablet weight

   20 g. Pack size 1 kg

   Start-up requirement

   Not published

   Dispenser compatibility

   Not published

   Amazon reference

   B01BMS82IA (one reference across 4 Amazon marketplaces)

   EAN

   8427370760259

   • The product name states the two things that matter most: slow, and 20 g
   • Gre is a pool-trade manufacturer with a skimmer and a chlorinator elsewhere in this catalogue
   • No bullets at all — the title is the whole listing

   Best for: A Gre pool or hot tub already using the brand’s other products

   Check price on Amazon
6. 

   HYDROSAL DisySal Brom Tablet 20 g

   Twenty-gram slow bromine tablets for small to medium pools and warm-water basins, naming six hot tub brands it suits and stating that a dosing float is not included.

   Active content

   Not published — as with all seven products in this family

   Tablet or granule format

   Tablet, slow-dissolving bromine

   Tablet weight

   20 g. Pack size 1 kg

   Start-up requirement

   Not published

   Dispenser compatibility

   Usable directly through the skimmer where one is fitted, or with a dosing float — the float is stated NOT included

   Amazon reference

   B07QCVVJ4R (one reference across 4 Amazon marketplaces)

   EAN

   8034792010017

   • The only listing here to state that a dosing float is not included
   • Names the hot tub brands it suits: Teuco, Jacuzzi, Hafro, Glass, Dimhora, Intex, Bestway
   • No dose, no active content, no registration number

   Best for: A small or medium heated pool or a named-brand hot tub, where the float is already owned

   Check price on Amazon
7. 

   Metacril BromShock granulate 1.5 kg

   The only granulate on this shelf and the only bromine activator: a shock product for initial and corrective treatment, stated to work in water up to 30 °C and in hard water.

   Active content

   Not published — as with all seven products in this family

   Tablet or granule format

   Granulate — the only one in this family. The six others are 20 g tablets

   Tablet weight

   Not applicable. Pack sizes stated as 750 g, 1.5 kg and 3 kg; this is the 1.5 kg

   Start-up requirement

   This IS the start-up product. Stated for initial and shock control of water quality and as a bromine activator

   Dispenser compatibility

   Not published as a route. Stated to give an oxidative and cleaning action in hot water up to 30 °C and in hard water

   Amazon reference

   B07P19WBWR (one reference across 5 Amazon marketplaces)

   EAN

   8034900000022

   • The only bromine activator on this shelf, which a bromine system needs at start-up
   • Publishes a temperature limit — effective up to 30 °C — which no tablet here does
   • Not a substitute for the tablets — it is the complementary half of the same system

   Best for: Starting a bromine system, or correcting one that has lost control of the water

   Check price on Amazon