Hot tub water balance guide

By balancing the hot tub water you are creating the right conditions for bather comfort, chemical efficiency and equipment protection. A number of factors are involved in balancing the water but the main areas are : Calcium Hardness, Total Alkalinity & pH

Calcium Hardness

This will vary depending on where you live and where your water supply comes from and it is very important that the correct level is established. As a guide soft water tends to be low in Calcium Hardness and hard water more obviously is high. The level should be checked each time you top-up or refill the spa with fresh water.
The ideal Calcium Hardness level for spas is between 100 - 200mg/l.
When it is below this level the water could be corrosive which could lead to damage of plant equipment such as the heater. If this is the case apply Hardness Plus to achieve the correct level.
When it is above this level the water has a tendency to appear cloudy and also calcium can precipitate out and deposit itself on the spa shell finish, heater element, cartridge element & within pipework. If this is the case apply No Scale to achieve the correct level.

Total Alkalinity

This will again vary depending upon your water source so must be checked each time fresh water is added. It acts as a buffer to prevent pH change and if the level is too low the pH will fluctuate widely, if too high pH adjustment will be difficult to effect.
The ideal Total Alkalinity for spas is between 125 - 150mg/l.
When it is below this level not only will pH fluctuate but the water could be corrosive, cause damage to equipment and be uncomfortable to bathers. Use pH Plus to raise levels.
When it is above this level not only is pH difficult to adjust but also the water could be scale forming and clarity impaired. Use pH Minus to reduce levels.

pH Levels

Regular pH checks are an essential part of your spa maintenance routine using Test Strips.
The pH scale has a range of 0 - 14 with 0 being very acidic, 7 being neutral & 14 being very alkali. For spas the ideal range is between 7.4 - 7.6, this being slightly alkaline to protect the spa and prevent equipment corrosion. This also provides the most comfortable conditions for bathers and good sanitiser efficiency.
If the level is below 7.4 use pH Plus to raise the level.
If the level is above 7.6 use pH Minus to reduce the level.

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