Optimal pH in the pool: the facts

Bathing in your own pool is a great thing. However, so that the pleasure does not turn into displeasure, the water quality in the swimming pool must be checked. A quality mark for this is the optimal pH value in the pool.

PH value

The pH value is an important indicator of the water quality, as it provides information on whether the pool water is acidic, neutral or alkaline. A value above 7.0 is referred to as hard (alkaline) water, below 7.0 it is referred to as soft (acidic) water. Swimming pool water is neutral if it has a value of 7.0. This is also the quality that is considered optimal for the pool water.

Note: If the water in the swimming pool is acidic or alkaline, this can have a negative impact on people and the pool. For example, one of the facts is that the effectiveness of disinfectants is weakened.

Measure pH

There are various options for establishing the facts (acidic, neutral or alkaline), such as:

• Manual test kit
• Electronic measurement devices

Since the pH value is not a constant variable but can change quickly, you should check it once or twice a week. Because water temperature, bathing frequency (hair, flakes of skin, sunscreen) and environmental influences (such as rainwater, Pollen, leaves), but also the addition of disinfectants and flocculants affect the pH value the end. That is why you should check a few hours later after the administration of chemical agents whether the pool water is in the optimal pH range.

Manual test kit

If a test kit is used, the quality of the water in the pool can be determined using a color scale.

Electronic measurement devices

Electronic measuring devices show the value on a display. Because they measure more accurately than liquid test kits or tablets, these test procedures are recommended. In automatic measuring systems, a probe measures the pH value of the swimming pool water. If a deviation from the optimal range is found, a correction is made. Such pH metering systems are commercially available as part of salt electrolysis systems and chlorine metering systems or as additional modules.

Optimal pH range in the pool

It is ideal for the pool when the pH value is almost neutral. Therefore the value should be between 7.0 and 7.4. Some pool experts see the range even narrower, namely between 7.2 and 7.4. The advantages of having the ideal pool water pH are:

• best development of water care products
• highest comfort factor for people

pH too low

If the pH value in the pool is below the optimal range, the negative consequences are often:

• increased risk of corrosion on metal parts of the swimming pool
• Inhibition of the action of flocculants
• Appearance of an increased smell of chlorine
• Damage to the filter pump
• Irritation of eyes, skin, mucous membranes and hair

pH too high

If the pool water moves in the alkaline range, this can also be harmful to the skin and the pool:

• Impairment of the protective fat and acid mantle of the skin
• Irritation of mucous membranes and eyes
• Lime deposits / limescale deposits (cloudy pool water, clogging of the pool filter)
• Favoring the development of algae
• Inhibition of the action of flocculants and disinfectants
• Reduction of the disinfecting effect of chlorine
• unpleasant odor development

Note: Measured values ​​above 7.4 ("too high") Occur far more often than below ("too low„).

Correct the pH value

If the pH value measured in the pool is outside the optimal range, it should be corrected. For this, chemical agents that restore the ideal value are used. Depending on which goal is to be achieved, come

• Countersink or
• Lifter

for use. The following rule of thumb applies to the dosage: For ten cubic meters of swimming pool water you need 100 grams of sinker or Lifter to correct the value by 0.1.

Note: Since these water care products take several hours to unfold, you should take a control measurement after 24 hours.

frequently asked Questions