Soft water is better for tea
Water can be categorised into the hard and soft water. For tea brewing, the simple guideline is water that contains more than 8mg/L of calcium and magnesium ion is hard, less than that, soft. Except for the rain, snow, and distilled water, all spring water from nature is hard. However, hard water can be softened through boiling.
Spring water is in a constant state of motion and filtered by sand and rocks. It is clean, stable in nature, and tastes fresh with a pleasant sweetness. It is ideal for brewing tea. However, it is best to use the spring water while it is still fresh and from a non-contaminated source.
Rain and snow
For Chinese ancestor, rain and snow are “sky spring”. However, due to air pollution, one should be sure of local air quality first.
Tap water is most convenient and available. However, it should be filtered to remove chlorine and minerals.
Mineral water has higher mineral content which gives its taste. However, this could affect the true taste of tea. Hence mineral water is not recommended for tea brewing.
It is a processed water. Although its pureness is unquestioned, it is relatively expensive and is not better than other types of water. It is not widely used in tea brewing.