Water : The Secret to Perfect Tea

Posted by Zach Mangan on

A guide to understanding how water can help you improve the taste and aroma of your Japanese Tea


The perfect cup of tea requires two things, great tea and great water. Water quality, while often overlooked, plays a key role in the tea’s final taste and aroma: mediocre tea brewed with the correct type of water will taste better than expensive tea brewed with poor quality water. After all, a cup of tea is almost entirely water. Make sure you are getting the most out of your tea by using the right water.

Spring water, a safe bet

At Kettl, We always start with fresh spring water (We use Poland Spring at our shop and at home). We find the PH and TDS (Total Dissolved Solids) perfect for brewing all styles of Japanese tea. If your tap water is from a clean source and not overly hard or soft, a simple carbon filter is a perfect solution.

Water on the softer side is best for brewing Japanese tea - look for a water with a TDS of about 30 - 80 PPM. Water with an aftertaste (chlorine, metallic, etc) should always be avoided. A PH reading of around 7 is ideal.

Poland Spring water - a TDS of 44 is perfect for Japanese Tea

Hard water contains high levels of calcium and magnesium which can suppress the aroma and taste of your tea. Water that is overly hard can't easily be remedied by a home water filter like Pur or Brita as they really only remove unwanted aroma and flavors but don't do much for mineral content. On the other hand, if your water is too soft or lacks any mineral content at all, adding charcoal or river stones directly to your water pitcher can balance the mineral content.

Pro tip: A simple way to find out if your water is hard or soft is to fill an empty plastic bottle half full of water and add a few drops of dishwashing liquid. Screw the cap back on the bottle, and shake vigorously. If water becomes foamy with bubbles your water is softer and suitable for brewing tea. If the soap ends up on the top of the water as a shiny film, the water is hard.


The color and aroma of tea is extracted differently according to water quality and makeup.

Poland Spring on the left (lighter) vs Volvic on the right (darker)

If you are having trouble finding the right balance, or feel your water is unsuitable even after trying these remedies, bottled water is a great alternative. Poland Spring, Ozarka and Volvic are some reputable brands of water that make great tea. We often brew tea side by side using bottled water and our own NYC filtered tap water as a comparison and find that the differences can be quiet notable. For example, waters such as Evian produce very little foam when making matcha (due to an incredibly high TDS) while Ozarka produces a fine, creamy foam. Both Volvic and Poland Spring each produce delicious tea, but Volvic tends to create a stronger color and deeper flavor than both NYC tap water and Poland Spring. But as We mentioned, the balance of flavor, aroma, and color feels perfect to us when we use Poland Spring - give it a try!

Taking some time to learn about your water will certainly improve your tea drinking experience and you might be surprised how much it improves the flavor and aroma of your Japanese tea. Have fun and enjoy the journey!

Sencha with a perfect color, flavor, and aroma - brewed with Poland Spring

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