Mr Koizumi GH/KH+ Premium quality Buffer. It is important to maintain these values at the right levels (GH between 8° and 12°; KH between 6° and 11°) in order to prevent acidification of the water. Dosage: 100 grams per 1000 litres, Raises the GH by 3° to 5° and the KH by 2° to 3°.
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