General Information about Water treatment Put the stones in a water jar (1-2 liters) and fill it up with tap water. The water shall be left for about half an hour (or longer) before drinking it. Only use drummed stones because raw stones are not suitable for water treatment due to their potential of splintering which can cause harm to you and the water jar. The chemical composition of the mineral is crucial for water treatment, the size of the mineral does not matter. After approximately 6-9 months the stones shall be exchanged.