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Pool and Spa Chemicals: An integral part of a water maintenance program

Chemicals should be stored in a cool, dry, ventilated areas, such as an appropriate backyard structure, well out of reach of children and pets.
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2. Water balancing products
Proper water balance is necessary to protect the surface of your pool and/or hot tub and equipment (e.g. pump, filter, heater, etc.) so they will last longer. Balancing your water will save you money and is necessary regardless of the sanitation and oxidation system you are using. There are five factors that affect water balance:

  1. pH
  2. Total alkalinity (TA)
  3. Calcium hardness (CH)
  4. Temperature
  5. Total dissolved solids (TDS)

If one or more of these parameters is low, then your water is corrosive. If one or more is high, then your water is scaling. The only way to know the level of these parameters is to test your water. The most accurate method is to have a professional perform a water test.

pH—proper range 7.2 to 7.8
pH is a measure of acidity. The lower the number, the more acidic the water is, while the higher the number, the more base the water. Keep in mind, seven is neutral. The pH of the human eye is approximately 7.5. Thus, pool and/or hot tub water has been adjusted upward to make the water more comfortable for bather’s eyes. If your eyes are red and itchy after going for a swim or soaking in the hot tub, check the pH.

  • If the pH is low, use a pH increaser.
  • If the pH is high, use a pH decreaser.

TA—proper range 80 to 120 parts per million (ppm)
TA is the measure of the water’s ability to keep the pH in the proper range. If the TA is low, the water’s pH will fluctuate wildly. On the other hand, if the TA is high the pH will always be high (8.4). Therefore, it is important to always adjust the TA first, as the pH will self-adjust to the proper range in most cases.

  • If the TA is low, use a TA increaser.
  • If the TA is high, use a TA decreaser.

CH—proper range 200 to 300 ppm
CH is a measure of the dissolved calcium in your pool and/or hot tub water.

  • If the CH is low (soft water), use a calcium increaser.
  • If the CH is high (hard water), use a calcium sequestrant (holds calcium in solution until the water is filtered or backwashed).

Calcium cannot be removed from your pool and/or hot tub once it is present; however, it can be sequestered to prevent it from depositing on surfaces and equipment (i.e. scale).

The higher your pool and/or hot tub water temperature
is, the more likely it is to scale. On the flipside, the lower the temperature is, the water tends to be more corrosive.

  • For pools, set the temperature as per bather comfort (typically between 25.5 and 28.9 C [78 and 84 F]).
  • For hot tubs, set the temperature as per the safe bathing guidelines based on length of use. For example, 40 C
    (104 F) for a 15 minute soak, 38.9 C (102 F) for 30 minutes, 37.8 C (100 F) for 45 minutes, and 37 C (98.7 F) for an unlimited soak.

TDS—ideal range 300 to 2000 ppm
TDS is the accumulation of chemicals added to the water. This is more of a concern in a hot tub because of the smaller water volume. Should these parameters go awry, this problem can be corrected by diluting the pool and/or hot tub with fresh water.

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