Different Types of Water and How They Change Tea

Selecting the right water type to brew your Japanese Green Tea

This article was last modified November 4th, 2021. by Yuki

water types

There's many different types of water. Many attributes.

Like mineral water or tap water. "Soft" water or "Hot" water. What's the pH? How does Chlorine have an effect?

So it's not only the temperature when it comes to infusing Japanese tea. It's important to know the exact type of water you want to use.

Here we'll go into all you need to know for choosing the best water to make Japanese Green tea.

water in a cup

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

It is said that the best water for brewing Japanese Green tea is a Slightly Acidic water (pH 6.0 - 7.0) with a water hardness of 30 to 80 – which is a moderately soft water.

Why? Let's consider the chart below.

Relationship between the water and the taste of Japanese green tea

Water Type Effects to the taste

If the water it too hard

The taste and aroma becomes lighter if water becomes harder. The hardness tends to put a muffler on those notes.

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

If the water it too acidic

While a slightly acidic water is ideal for Japanese Green tea, it shouldn't be too acidic.

If too acidic, the tea may develop a more sour taste.
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, ideall, keep the pH around 6.0 - 7.0.

Chlorine content in the tea

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

It's important 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.

tap water in singapore

How is Tap Water in Singapore

The drinking water in Singapore is also a moderately soft water is works well for brewing Japanese Green Tea. However, the acidity of Singapore’s tap water is slightly basic at an average pH of 8.1 according to PUB Singapore's National Water Agency. This means that the tea can become a little bitter. It would be good if you have an ionizer to adjust the pH levels.

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

bottled mineral water

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. This may not be ideal for brewing Japanese Green Tea either. Hard water will make the tea taste light and reduce the aroma as well. Make sure to check and buy soft water.


What is a good way to reduce the temperature of water after boiling it?

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

I live in Singapore and I have no way of changing the slightly basic water to a slightly acidic water. Will I not be able to make 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!

Author Yuki


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.