Water: The Key to a Great Cup of Coffee
Kenneth Thomas, Courtney Orlando
Honestly, the coffee I make at home is never as good as the coffee I get from the coffee shop. Before I got into coffee, I just figured a tattooed barista from a specialty coffee shop had some magic wand behind that bar that made their coffee taste better. Turns out they did have a magic wand - their water.
I used to blame everything except the water.
If a cup tasted off, I’d start running through the checklist in my head:
- Maybe the water temp was off
- Maybe I messed up the grind
- Maybe I needed better equipment (and I can't tell you how many times I used this excuse to justify buying more coffee gadgets!)
So I’d tweak things. Buy something new. Adjust again.
And sometimes it helped… but sometimes it didn’t. But most of the time, it still didn't taste like coffee from a specialty shop.
Then one day I met Taylor Minor with Third Wave Water and he suggested it might be related to the water I was using. He gave me a dialed-in mineral packet to place in a gallon of distilled water.
Boom! That was it!
The cup tasted completely different cup.
Sweeter. Richer. More complex.
That’s when it clicked:
- I had been obsessing over the 1–2% of the cup… and ignoring the other 98%...the water.
A specialty coffee shop worth its weight in coffee grounds usually has a special water filtration system, because coffee needs the right balance of minerals to extract the right stuff in the right amount out of the coffee grounds themselves. Most municipal water systems don't come close to the right balance...so the extraction is off...and your cup of coffee at home then tastes different than the same coffee at a coffee shop...all because of your water.
Here's the good news, though: You can have just as good of a cup of coffee at home as in the fancy specialty coffee shop when you start with the right water.
And these days, the right water is easily accessible. So, you may ask, why is my coffee at home still not good? Maybe I'm lazy. I just use whatever water I have. Maybe I shouldn't do that. Maybe this article will even convince me how easy it is to make great coffee at home.
Quick Answer: What Is the Best Water for Coffee?
The best water for coffee is clean, balanced water with the right amount of minerals—not too pure, not too heavy.
Water doesn’t just carry flavor—it extracts it. And when the mineral balance is right, your coffee tastes sweeter, clearer, and more balanced.
The Big Idea
Water isn’t just an ingredient in coffee - it’s the main ingredient.
Brewed coffee is about 98–99% water, which means your water doesn't play a supporting role...
Water brings main character energy to your cup.
Good water pulls out the best parts of coffee:
- Brightness
- Sweetness
- Body
How about bad water?
Bad water is like that passive aggresive friend who gaslights you saying stuff that sounds good, but you know deep down that something's definitely off...but it's not off enough for you to intervene, so you just settle for a friendship that's just kinda meh.
Even the best coffee in the world can taste flat or bitter if the water isn’t right.
The Science Behind Coffee Water
Water extracts coffee flavor through dissolved minerals. These minerals determine what shows up in your cup—and what doesn’t.
Magnesium: The Flavor Enhancer
Magnesium is one of the most important minerals for extraction.
- Bonds easily with acids and sugars
- Enhances brightness and sweetness
- Creates a more vibrant, lively cup
If your coffee tastes bright and expressive, magnesium is doing a lot of the work.
Calcium: The Body Builder
Calcium extracts heavier compounds.
- Adds body and texture
- Brings out chocolatey and nutty notes
- Creates a fuller, creamier mouthfeel
Too much, though, and things can start to feel heavy—or even bitter.
Bicarbonates: The Balancer
Bicarbonates control acidity.
- Act as a buffer, softening sharp acids
- Help create balance
It's like goldilocks - everything needs to be 'just right':
- Too many minerals? Coffee may taste flat (sweetness disappears)
- Too few minerals? Coffee may taste overly sharp and sour (brightness overdone)
Balance is everything.
Why “Pure” Water Isn’t The Answer
It’s tempting to think distilled or ultra-pure water would make better coffee.
It doesn’t.
Here's the thing:
- Distilled water has no minerals
- No minerals = poor extraction
- Result = thin, hollow, lifeless coffee
The goal isn’t purity - it’s balance. And balance comes from the right amount of extraction...which comes from the right amount of minerals.
How to Improve Your Coffee with Better Water
The good news? This is one of the easiest upgrades you can make to your coffee game.
Do me a favor and check out Third Wave Water. They've got a simple answer for your water game - basically order the perfectly balanced mineral packets from them and place in 1 gallon of distilled water from the grocery store - that's it!
That one easy move will bump you up to cafe-level water instantly.
If you ever have a chance to come by Umble Coffee's headquarters, or if you're just curious, we use a reverse osmosis system to dial in the perfect mineral content for the water we use on a commercial level.
Application: Try This Yourself
If you want to taste how much water matters:
- Brew the same coffee with your regular water and distilled water with your Third Wave Water of choice in it
- Let them cool slightly
- Taste them side by side
- Pay attention to brightness, sweetness, and body
We bet you’ll notice a big difference.
The Takeaway
- Coffee is 98–99% water
- Mineral balance in water is one major driver of proper extraction
- Magnesium enhances sweetness and brightness
- Calcium adds body and depth
- Bicarbonates control acidity/brightness
- Better water = better coffee (period!)
Big Picture
Most people try to fix their coffee by changing everything except the thing that matters most...WATER.
But once you get your water right, everything else in your cup starts to make sense:
- Complexity increases
- Confusion and unpredictability decreases
- Coffee becomes more all-around consistent
At Umble, we care about every step—from the farm to the roast to the water it’s brewed with—because all of it shapes what ends up in your cup.
If you want better coffee, start here.
- Grab a bag of freshly roasted coffee from us
- Try brewing with better water
- Join our email list for simple ways to level up your brewing
Because sometimes extraordinary coffee isn’t about having the best gear. It’s about understanding what’s in your cup and how it impacts your coffee.
I'll have to be honest: I'd forgotten really how easy it is to make cafe-level coffee at home simply by using the right water. I'm going to order some Third Wave Water packets and go by the grocery store on the way home for a gallon of distilled water. I'd gotten lazy...but tomorrow I'm going to brew a nice Kalita Wave pour over with the right water. I want to live a story worth telling, and I believe that starts with an extraordinary cup of coffee!
Hip, Hip, Hooray for Great Coffee!
All the best,
Kenneth
PS - At Umble, we don't profit from suggesting you use a certain product, like Third Wave Water. We promote it because it's a great product, and one we think you should use to level-up your water game. Simple as that!