Bromine granules are great way to boost bromine levels in a hot tub running on bromine tablets or with an in-line system such as Spa Frog. See 'Directions for Use' for more detaile instructions. Bromine can be re-generated in the water with a shock dose using Non Chlorine Shock or Bromine Granules whereas when Chlorine is used up, it will no longer work to sanitise your hot tub.
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