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Yuki. I
Jun 24th, 2024

Different Types of Water and How They Change Tea

Selecting the right water type to brew your Japanese Green Tea
When it comes to brewing Japanese teas such as sencha or Matcha, water may be deeper than you think. Water has several different attributes, and they all affect the taste of tea.

You may be familiar with the difference between mineral water and tap water, and you may have heard the differences between "Soft" and "Hard" water. Are you aware that there are slightly different pH levels depending on how you source your water? Then there's water with Chlorine and without.

Therefore, water temperature is not the only factor important when infusing Japanese tea. Knowing the exact type of water you want to use is beneficial, especially when you have a really special tea and want to enjoy its taste to the max.

Here, we'll discuss everything you need to know about choosing the best water to make Japanese Green tea.

What we'll Learn

In this article

  • Ideal Acidity and Hardness of Water for Brewing Japanese Green Tea.
  • How is Tap Water in Singapore?
  • Can Mineral Water be used for Japanese Green Tea Brewing?
  • FAQ

The Ideal Acidity and Hardness of Water for brewing Japanese Green Tea

The best water for brewing Japanese Green tea is slightly acidic (pH 6.0 - 7.0) and has a water hardness of 30 to 80, which is moderately soft.

Why? Let's consider the table below.

Relationship between the water and the taste of Japanese green tea
Water Type
Effects on the taste
If the water it too hard

If water becomes harder, the taste and aroma become lighter. The hardness of the water tends to muffle those precious tasting notes.

The ideal water hardness is 30 to 80, which would be categorized as moderately soft water.

If the water it too acidic

When it comes to Japanese Green tea, the water should be slightly acidic, but not too much. The tea may develop a more sour taste if it is too acidic.

The ideal acidity is pH 6.0 - 7.0

If the water it too basic

On the other hand, If the water is too basic, the tea may become bitter. 

Again, ideally, keep the pH around 6.0 - 7.0.

Chlorine content in the tea

Japanese tea is a delicate drink so that you will taste the chlorine content in the tea.

It's essential to remove the chlorine by boiling the water at 100 degrees.

Even for Japanese tea that requires a lower water temperature than 80, you'd still want to boil it first before cooling the water to bring down the temperature.

This nature of the tea is why all our instructions recommend boiling the water once, even for a tea with low brewing temperatures, such as Gyokuro.

How is Tap Water in Singapore?

Singapore's drinking water is also moderately soft, which works well for brewing Japanese Green Tea. Therefore, the hardness of the water is not an issue.

However, according to PUB Singapore's National Water Agency, the acidity of Singapore's tap water is slightly basic, at an average pH of 8.1. This means that the tea can become a little bitter. It would be good if you had an ionizer to adjust the pH levels. However, this difference is so slight that I wouldn't stress too much about this.

Singapore's tap water also contains 2 to 3 mg per liter of Chlorine. Make sure you boil the water before you use it to infuse the tea. If not, the effect of chlorine will be recognizable in the tea – not a pleasurable thing to have.

Can Mineral Water be Used for Japanese Green Tea Brewing?

Many mineral waters sold are hard water, which contains high levels of magnesium and calcium. Although this is expensive water, it is counter-intuitive because it may not be ideal for brewing Japanese Green Tea.

As the table above mentions, hard water will make the tea taste light and reduce the aroma. Therefore, it doesn't justify going out and buying expensive water to brew. Thus, as mentioned above, I recommend using tap water in Singapore. If you insist on purchasing water outside, I recommend water bottles containing drinking water rather than mineral water for brewing Japanese tea.

Either way, as much as possible, check and buy soft water when you go out to purchase it externally.

Can Mineral Water be Used for Japanese Green Tea Brewing?

What is a quick and easy way to reduce the water temperature after boiling it?

A: There are several ways to do this. Moving the water into a different bowl will reduce the temperature by 5 degrees Celsius or so. It will do the same by leaving it out for 1-2 minutes. You can combine these methods to achieve your desired temperature. You can read more details about water temperature in this article.

I live in Singapore and have no way of changing the slightly basic water to slightly acidic. Will I need help making good Japanese tea?

A: Don't worry about it. Slightly basic water won't make the tea taste bad at all. You'll still be able to enjoy a nice cup of Japanese tea with tap water in Singapore. Just make sure you boil it at 100 degrees first!


Yuki is the Editor-in-Chief AND Community Manager at Tealife. He bleeds Japanese Tea and loves being a part of the Japanese Tea journey of others. Writes, does events, conducts tasting sessions, drinks, drinks and drinks tea! Easily accessible - hit him up on whatsapp (+65) 85882980.