The stabilizer for the pH

The carbonate hardness is the stabilizer for the pH. With low carbonate hardness the pH is unstable and can change rapidly again and again. The optimum for the most aquariums and ponds is 4 - 8 °dKH.

To reduce the hardness, we recommend AQUAVITAL BLACK PEAT or AQUAVITAL GRANU-PEAT. To increase the hardness place calcium contained stone or gravel (e. g. coral sand or marble stone) in the water.