How to lower the pH value correctly

How to lower the pH value correctly?

Since the pH value can be lowered easily or with difficulty with water of different hardness, the pH value should be measured first. It is essential to use an electronic pH tester or measuring tablets for this purpose. Do not use test strips. Test strips may have been exposed to different humidity levels during production and have therefore already reacted with the humidity level. Generally, they show very inaccurate values.

Always remember: When the water is heated, the pH value rises. So measure and adjust the pH value only after the first heating.

After measuring the pH, add a small amount of pH minus to the water. Start with one tablespoon per 1000 litres. Let the pumps run during the addition. Even after the addition of the pump, the pH-minus can be evenly distributed in the water so that the same pH value prevails everywhere in the water. After approx. 2 minutes, measure the pH value again and estimate the required amount of pH-minus on the basis of the difference to the first measurement and add to the water. This procedure may have to be repeated several times.

The ideal pH value for the whirlpool is between 6.8 and 7.2. If you have accidentally lowered the pH value too far, wait a day. In the initial phase, the pH value rises by itself. With hard water, the pH value should always be below 7.0. 6.5 to 6.8 are ideal. By the value under 7,0 one can exclude that it comes to a lime formation.


Always measure and adjust the pH value after adding the cleaning agents. UltraShock is a strongly alkaline agent and can therefore increase the pH value. SpaBalancer is a slightly acidic agent and can therefore lower the pH value.

Depending on the water hardness, the pH value rises again. The harder the water, the faster and the higher the pH increases. With hard water it can happen that you have to adjust the pH-value daily at first. Since the pH value rises again very quickly with very hard water, it can be useful to adjust the pH value to 6.5 or even 6.0 so that it does not rise to 8 to 9 or higher overnight.

How long does the pH value rise?

With soft water, the pH value can remain stable after just one week. The harder the water, the longer the pH value will increase. With very hard water, this can take up to 2 months before the pH value remains stable. Only when the excess carbon dioxide is outgassed does the pH value remain stable.

What should I do to lower the pH value?

Our pH-Minus Liquid is highly recommended. It is very easy to dose. It also has a quadruple effect:

  1. It lowers the pH valuet
  2. It converts calcium ions into water-soluble salts
  3. It dissolves existing limestone
  4. It acts as a complexing agent for calcium, iron, copper etc.. It binds these substances and makes them filterable.

Since very hard water requires a large amount of pH reducer, you can also switch to the cheaper granulate, which you can buy everywhere.

 What exactly is the pH value? >>

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