Is Bromine Acidic or Basic

After being around water treatment and pools soo long I’ve often seen alternative sanitizers but what really makes chlorine so popular is its abundance and the fact that most pool owners are unaware of other trustworthy viable alternatives like Bromine which works mainly the same as Chlorine. Is Bromine Acidic or Basic?

Bromine will reduce the pH level of your swimming pool, making it more acidic, the effect is only a small difference from that when using chlorine, still, it’s easier to make adjustments. As a result, you can achieve the ideal pH balance of your pool water’s chemistry more easily.

People can use Bromine as an oxidizer that will remove electrons from another compound, algicide a compound that kills algae, or a sanitizer or disinfectant, basically just like chlorine doing the same job in your swimming pool.


Is Bromine Acidic or Basic


Bromine has a low acidic pH of around 4, and using bromine tablets will slowly lower pH and alkalinity over time, requiring additions of a base chemical to raise pH and alkalinity. The same can be said for chlorine tablets, which have a pH even lower, around. Bromine is far less affected by pool or spa water’s basic pH than chlorine and is able to be an active sanitizer at high ph levels of 7.8 – 8.2.


Bromine Element: Chemistry Acid Substances

Testing for bromine chemistry is accomplished with the use of a chlorine test kit, or a DPD chemistry test kit. There are Bromine test kits labeled as “Bromine Test Kit”, but they are simply chlorine test kits, slightly modified for use with Bromine elements. If you are using a chlorine color comparison chart with test strips, or matching colors with a test kit comparator for chlorine, multiply the result by 2.25 to convert a chlorine test to a bromine test.

Aqueous hydrogen bromide is known as hydrobromic acid, which is a strong acid (pKa = −9) because the hydrogen bonds to bromine are too weak to inhibit dissociation. When added to water, bromine forms hypobromous acid. Hyprobromous acid is a weak acid.


  • Where is Bromine Found 

  • Bromine is found naturally in the earth’s crust and in seawater in various chemical forms. Bromine chemical can also be found as an alternative to chlorine in swimming pools. Products containing bromine are used in agriculture and sanitation and as fire retardants (chemicals that help prevent things from catching fire).
  • Bromine has a large variety of uses including weak acids in agricultural chemicals, insecticides, dyes, pharmaceuticals, flame-retardants, furniture foam, gasoline, plastic casings for electronics, and film photography, according to the Royal Society of Chemistry.
  • Some bromine-containing compounds were historically used as sedatives (drugs that can make people calm or sleepy). However, these drugs are for the most part no longer found on the market in the United States.
  • Following the release of bromine good oxidizing agent and nonmetal into solutions of water, you could be exposed by drinking the contaminated water.
  • If food becomes contaminated with bromine, you could be exposed by eating the contaminated food.
  • Following the release of bromine element gas into the air, you could be exposed by breathing the fumes.
  • The risk of skin exposure to bromine could occur through direct contact with bromine liquid or gas.
  • Bromine gas is heavier than air, so elements would settle in low-lying areas.


What are the differences between Chlorine vs Bromide in a pool

  • Chlorine(Cl) works faster to kill contaminants but for a shorter period of time, as it dissipates faster.
  • Bromine(Br) a more stable chemical kills contaminants more slowly but for a longer period of time & can help keep H2O chemistry .………………………….. Read more



How do you Switch From Chlorine to Bromine Sanitizer

To switch from chlorine to bromine:

  • Stop using chlorine
  • Empty pool to ¾ min. level
  • Clean filtration system by backwashing
  • Make sure there is no more Chlorine stabilizer (CYA) in H2O
  • Begin using bromine tablets
  • Replace floater/chlorinator to prevent chlorine residue…………………………………………….. Read more

What Alkalinity Should Bromine Pool Water Have


Taylor Service Complete Pool Water Test Kit K-2006C

Bromine tablets generally have a pH around 4, therefore, pH adjustment to the water will be necessary to maintain proper water balance. Even though bromine is effective over a wide pH range, it is important that the ANSI/APSP/ICC-11 recommended pH range of 7.2 to 7.8 and alkalinity range of 60 to 180 ppm be maintained.

According to ANSI/APSP/ICC-11Standard for Water Quality in Public Pools, the ideal range for bromine is 3 to 4 ppm for pools and 4 to 6 for spas. Test kits designed for measuring bromine are widely available.

Note that when testing for bromine with a chlorine test kit, the reading should be multiplied by 2.25 to obtain the bromine concentration. Additionally, Oxidation-Reduction Potential (ORP) may be used to test bromine-treated water; however, the reading will be lower than that obtained for chlorine.

Current test kits and test strips will not distinguish between free and combined bromine. Both will test as free. Take a look at a great test kit made by Taylor sold on Amazon and recommended by us here at MyWaterEarth&Sky Taylor Service Complete Pool Water Test Kit K-2006C


Testing for Bromine in Pools


Even in tablets where chlorine is a component, or in systems that employ sodium bromide and chlorine together, HOBr is still the primary sanitizer present in the water. This occurs since hypochlorous acid (HOCl) readily reacts with bromide ions in solution to make a new molecule of HOBr and a chloride ion (Cl- ).

Bromine has a low odor and is effective over a wide pH range. In the recommended pH range for swimming pools of 7.2 to 7.8, HOBr formation remains over 90 percent. At a pH of 8.0, HOBr formation is still 83 percent compared to HOCl formation from chlorine at 23 percent.

For this reason, in systems where pH may drift upward for short periods of time (i.e., hot tubs and spas) bromine is a popular choice

Bromine tablets are typically fed into the water via either a floater or a bromine feeder. Care should be taken when selecting the appropriate delivery system since the two predominant types of bromine tablets dissolve at different rates.

Once bromine is used in a pool, it will remain a bromine pool, even if bromine is discontinued and chlorine is used. A popular misconception is that the pool must be drained to switch to chlorine.

While that is the quickest method of converting a pool to chlorine, a pool with bromine or bromide ions can switch back to a chlorine pool over time. The greater the amount of oxidation and the greater the amount of sunlight present, the shorter the conversion time. Keep in mind that during the conversion process, chlorine demand will remain high.

As with chlorine sanitizers, it is recommended to periodically shock oxidize the water when using bromine tablets. Product label directions should be consulted to identify the type and frequency of supplemental oxidation treatments.

Bromine is an effective algaecide, particularly against difficult-to-control mustard and black algae, and its algaecidal properties are well known. Sodium bromide, as a source of bromine, has been EPA-registered as an algaecide.

However, sodium bromide alone will not kill algae. To be effective, it must be used in conjunction with an oxidizer, typically chlorine. If using sodium bromide as an algaecide, ensure that the product is EPA registered for that purpose and follow all label directions.

Bromine tablets, granular bromine, and bromine systems are oxidizers and must be handled properly. Avoid contact between bromine tablets or bromine compounds and easily oxidizable materials such as ammonia, urea, nitrogen-containing compounds, strong reducing agents, and other oxidizers regardless of their structure.

*Never place bromine tablets or compounds in any chemical feeder or floater with any other chemical, including chlorine.



 How to Raise Bromine Level in Pool?

  • Shock the pool if the bromine level falls below 2.0 ppm
  • Increase the dial setting on Brominators
  • Add pucks to floaters
  • Open bleeders on pool floaters
  • Increase the number of pucks in skimmers
  • Lengthen the pool’s pump run time .……………………………………………… Read more


JimGalloway Author/Editor



American National Standard for Water Quality in Public Pools and Spas


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