Spa Water Chemistry – Bromine Tablets | Spa Covers Etc.


Spa Water Chemistry – Bromine Tablets | Spa Covers Etc.

Spa Water Chemistry

Bromine: Chemical used to sanitize water. A level of 3.0 to 5.0 ppm should be maintained.

pH (potential Hydrogen): A scale of 1 to 14 that measure the alkalinity of the water. A reading below 7.0 equals acidic water and will cause etching of the plaster, staining and corrosion to the metal pipes and heater and could be irritating to swimmers. If the pH is above 8.0 the water will be cloudy, scale will build up along the tile and in the pipes. The filter will become clogged and circulation will diminish. A high pH also makes chlorine less efficient but Bromine works OK at a pH of 8.0. In A Fiberglass spa keep the pH at 8.0 or above.

Acid Demand: If the pH is above 7.8, use the #3 test solution 1-drop at a time to determine how much acid is required to bring the pH down to the ideal range of 7.4 to 7.6. Count the number of drops and compare against the chart in the test kit to determine how much acid. NOTE*** Dry acid is preferred when adjusting spa water.

Total Alkalinity: This is a buffer for the pH. The ideal range is 80 to 120 ppm. If the Total Alkalinity is above 120ppm the pH will drift up (above 7.8) and the demand for acid will be higher. If the Total Alkalinity is below 80ppm the pH will drift below 7.4 and Base will be needed to raise the pH on a regular basis. The pool will also be prone to blue stains.

Base: When the pH is below 7.4, a Basic (opposite of acidic) product will be added to the pool to raise the pH. The name of this product is Soda Ash. This should not be needed and only used if the chemicals are allowed to be out of range for extended periods of time.

T.D.S.: Total Dissolved Solids can be tested at the local pool store. Check every other month. The maximum reading is 2000 to 2500 ppm, if above 2500 ppm drain pool. T.D.S. is a measurement of ALL dissolved particles in the pool. Everything leaves some particles behind. Chemicals, dirt, people etc. all leave some TDS and over time the measurement rises. Liquid chlorine is the biggest contributor to this reading. When the pool has a high T.D.S. level people may complain the pool “tastes salty”. A high T.D.S. level won’t cause damage but will make the chlorine a lot less efficient and the cost of chemicals will be more.

ConditionerMade from Cyanuric acid and is used to preserve chlorine levels in the water. The ideal range is 40 to 80 ppm. This chemical is added when the pool is filled and on a periodic basis. Test for this chemical with a Cyanuric acid test kit. Not used with Bromine

Algaecides: Kills algae. Identify the color of the algae and the location of the algae. Common colors in California are Green algae, Yellow (mustard) algae, and Black algae.

Scale: Deposits of calcium on the tile and plaster, caused by high pH.

How to maintain Spa Water Chemistry
Using Bromine Tablets

Items Needed:

  • Bromine Test strips
  • 1” Floating Bromine Dispenser
  • Bromine Tablets (1”)
  • Sodium Bromide (1 oz added each time spa is drained and re-filled)
  • Leisure Time “Metal Gon” (Add 1 pint bottle each time the spa is re-filled)
  • Non-Chlorine Shock (often sold as Renew) (individual 1oz packets or 2lb bottle)
  • pH increase (Raises pH. Often sold as Spa Up)
  • Spa clarifier (Look for a product that is a 4 in 1 and contains enzymes)
  • Foam Down

Where to Buy: Purchase these items from a POOL SUPPLY…..NEVER PURCHASE SPA CHEMICALS FROM HARDWARE STORES!!!  Their products aren’t as good.

Weekly Maintenance:

Test spa water with test strips (designed for use with Bromine)

  • Dip test strip in water and hold flat for 15 seconds and compare colors to chart.
    (For best results do this out of direct sunlight)

Check the reading of the pH and Total Alkalinity first.

pH: Measurement of 7.4 to 8.4 is ideal for Bromine. If it is higher don’t worry. If it is lower add 1 cap-full of Spa Up, allow water to circulate for 15 minutes and re-test. Repeat if necessary (up to 3 times. If you cant get it to come up either drain spa and re-start or bring sample of water about 1 pint to your local pool supply and ask them to test it for free). If the water tends to be lower than 7.0 each time you test the water it is probably time to drain the spa water and start fresh.

Total Alkalinity:  Readings of 110ppm and above are desired. If the readings are below 80ppm drain the spa.

If the pH and Total Alkalinity are OK then proceed.

With a Bromine sanitized spa it will be very simple to maintain fresh clean water.

If the Bromine has a reading of 5.0 or better you have plenty of sanitizer.

If the Bromine Level is too high just remove floating bromine dispenser (the floater).

If the Bromine level is below 3.0, Verify that the floater has tablets (3 to 4 (or the equivalent of lots of little pieces of bromine)) and the floater is set to # 3 or # 4. (On the side of the floater are numbers, Close the floater until these numbers are exposed. Lock in place with locking ring.) Add tablets if necessary.

Adding 1oz of Non-Chlorine Shock (Renew) will instantly activate the Bromine in the water and you will have a healthy Bromine Reading (above 3.0).

Always wait 15 minutes before you add additional chemicals and always add chemicals with the filter on.


  • Dedicate a bathing suit to the spa and NEVER wash it. Laundry soap causes foaming.
  • Addjust a small shot of Foam Down if spa has Excessive foam (may cause cloudiness)
  • The Spa Cover is ESSENTIAL…. It prevents the sun from burning out the Bromine
  • Test the water 1 time per week and again before using it
  • Add 1 oz of Spa Clarifier each week to help the filter (preventative maintenance).
  • Using high pressure garden hose clean filter pleats each month
  • Drain Spa 3 to 4 times per year (it’s just a big bath tub).
  • Always add the chemicals to the water…never add the water to the chemicals!!!
  • Keep at a 2lb. container of Spa Up on-hand and hope the pH just stays high and that you do not need to add it at all.
  • Circulate the spa for approx. 3 hours per day
  • Don’t try to balance the pH. Its just too hard to do. Just keep it at 7.4 to 8.4 and if it goes higher don’t worry. Only pH BELOW 6.8 is bad for both your skin and the spa equipment
  • Trust your instincts…. If the water looks good and SMELLS good then you are probably OK. But if it SMELLS bad or is Cloudy or Discolored there is definitely a problem!
  • There may be strong fumes when you remove the cover if the spa is heated but that should go away immediately. Choking and coughing are not normal.
  • Bromine should be LESS of an irritant than Chlorine.

For More Info Call Spa Covers Etc. 949) 496-2883