When you brew tea, use water that has been boiled once.
When you brew tea in water that has not been boiled, the tea leaves will float and will not open completely, leaving mediocre tea.
Do not add cool water to reduce the water temperature. Always let water rest to cool.
In order to cool the hot water, it is ideal to use a hot water cooler or transfer to your tea cup to cool.
The water temperature fall around 10℃/50℉ by transfer boiled water into a tea cup or 湯冷まし：yuzamashi (special tea pot shaped bowl to cool water) one time.
☆To remove chlorine from tap water
Boil water for an additional 5 minutes after boiling or let your water sit overnight in a container to let the chlorine dissipate.
＞＞ How to brew hot green tea