Boiled and cooled tap water or purified water can be used for milk. Using tap water to flush milk, it is recommended to consider according to the local water quality, if the local water quality is good, it is possible to use tap water to flush milk, but must be boiled for 3 minutes to dechlorinate, cooled to about 40 ℃ and then used to flush milk. In the old neighborhoods, remote cities, living in high-rise tanks for secondary water supply families, tap water quality is relatively poor, it is recommended that the use of pure water for milk. No matter what water to brew milk, must be boiled and cooled to about 40 ℃ before brewing. Because too high a temperature will not only make the loss of nutrients in the milk, but also prone to scalding. If the milk is brewed directly without heating, the impurities in the water may cause diarrhea in the drinker. If you feel unwell while consuming milk, consult a doctor. People who are allergic to milk should not consume milk.