This is a water test to minotor the carbonate hardness in aquarium and garden pond.Rainwater penetrates the soil, at the same time washing out minerals such as carbonate and hydrogen-carbonate, which together form the carbonate hardness.
In a community tank we should have a hardness between 5 and 10 dkH. Malawi and Tanganyika cichlids need higher values.
The KH value can drift down with time and insuficient water changes, use Sera KH-Plus to safely increase the KH.
