whether the pond is filled with hard tap or spring water - sooner or later
the pond contains mainly rainwater. The KH-test proves that: Below 5° dKH
the water is not stable, that means that the plant respiration removes
carbonic acid from the water. If there is a lack of lime or carbon the
pH-value will rise to the same extend. In the evening it will often reach
a fatal level of above 9.0 pH. Clearly neither fish nor plants appreciate
this condition. Plants will stop the production of the vital oxygen
already at a pH-value of 8.6.
If this is an ongoing process the pond will 'die'. Sensitive
micro-organisms (there are many thousands of those in a pond) will suffer
first. Fish are more robust, however, the sensitive mucous membranes are
badly affected by heavy fluctuations of the pH-value. This enables viruses
to enter the fish body. The fish fall ill or even die. When pond mussels
die and water lilies and other pond plants will not continue to grow, this
is a sure sign that "Hardness
Plus" should be applied.
has to be done?
The addition of "Hardness
Plus" will immediately improve the water quality of a pond that
suffers from a low lime content (Don't forget to do the KH test!)
often do I have to treat my pond with "Hardness Plus"?
The carbonic compounds are being 'used up' as time goes by, i.e. through
addition of rainwater. Rainwater does not contain lime. A rise of the
nitrate level also reduces the carbon level. Plants and animals (mussels,
snails) use the trace elements contained in the pond water. The easy to
use KH-Test from the OASE Test Kit can quickly establish whether it is
necessary to reapply "Hardness
Plus". is the case if the measured level of dKH lies below 5° or the
pH-value lies below 7.0.
In case the test shows a pH-value below 7.0 (acidic) and the
done at the same time shows a level above 5° dKH add "Hardness
Plus". In this case other water compounds deceivingly show a level of
carbonates, which is in this constellation not really present.
activ "Hardness plus" plus
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