empirical water: Open Source Coffee Water - DIY!

empirical water: Open Source Coffee Water - DIY!

4 min read


Hi there. My name is Arby Avanesian, and I'm the developer of empirical water.

Are you familiar with Third Wave Water, Perfect Coffee Water, Lotus Water, Apax Lab, or Aquacode? How about DIY recipes from Barista Hustle, Scott Rao, Matt Perger, Jonathan Gagne, or Chris Hendon, among others?

Many of these folks have been instrumental in giving water its due credit in the process of brewing great coffee, and deserve recognition for laying the foundation.

Today, we build on that foundation. There is certainly room for advancement, given that those brew waters are optimized for mass production in the case of the branded products, and accessibility in the case of the DIY recipes. In other words, anyone can buy the constituent ingredients on Amazon and mix them into water in the same amounts as any of those products or recipes, with no extra steps.

Coffee water that's optimized for quality on the other hand, is a completely different animal. Enter empirical water, which pushes coffee water into the seriously under-explored territory of mineral compositions which are exclusive to naturally-occurring mineral water.

To make empirical water, it's going to take time, labor, equipment, and know-how. I'll provide the know-how, but you're going to have to do everything else yourself.

It's also going to take one key ingredient that you won't find in any coffee water brand on the market, until now.

The key ingredient

It's calcium carbonate. (Or magnesium carbonate, if you like magnesium dominant water.)

AKA chalk, AKA calcite, AKA limestone. The finest naturally-occurring mineral waters from around the world all contain calcium carbonate.

Disclaimer: I wasn't the first to use calcium carbonate, and I don't think someone could claim ownership of something like that.

But I do want to get the conversation rolling on the topic, because it's been flying under the radar for far too long. I want everyone reading this to enjoy coffee as much as I do, and for that to happen, you simply need to have calcium carbonate in your brew water.

How does it work?

If you want me to explain how calcium carbonate works, you have to understand that you're asking some random guy to put on his chemist hat and talk all science-y as a way to establish his authority and gain your trust. If you want me to attempt that, click here.

But the truth is, I'm just some guy who's been playing around with this stuff, and I'm telling you, calcium carbonate just works.

What does it actually DO?

Calcium carbonate makes all your brew parameters so much more forgiving, that brewing amazing coffee becomes as effortless as breathing. Coffee comes out tasting more natural and pure when calcium carbonate is present in the brew water. You can also extract much more flavor and aromatics from the coffee beans before encountering any level of bitterness or astringency.

It's the principal differentiator of empirical water, along with its constantly evolving nature. I'm a hobbyist at heart, and will likely never stop tweaking the recipe to get the most out of coffee with incremental improvements.

How to make empirical water GLACIAL profile

Feel free to download the spreadsheet  And edit as you see fit.

If all this looks like too much of a hassle, you can try a sample here.

Buffer Instructions

  1. Add 1000 grams of deionized water to a mixing container.
  2. Add 36.82 grams of sodium bicarbonate, and mix to fully dissolve.
  3. Add 4.55 grams potassium bicarbonate, and mix to fully dissolve.

Hardness Instructions

Here's where it gets a little more complicated.

You're going to need a way to carbonate your water. Pick up a carbon dioxide tank and a keg from a local homebrew shop. The following instructions are for a 15 gallon keg. If you want to use something smaller, just scale everything down.

  1. Add 51 liters of deionized water to the keg.
  2. Add 4.994 grams of magnesium chloride hexahydrate, then mix to fully dissolve.
  3. Add 22.958 grams of magnesium sulfate heptahydrate, then mix to fully dissolve.
  4. Add 8.370 grams of anhydrous calcium chloride, then mix to fully dissolve.
  5. Add 16.089 grams of calcium carbonate.
  6. Close the keg and force carbonate it at 120 PSI. Vigorously agitate the keg by rolling it back and forth. This may take a good 10-15 minutes until you can no longer hear gas flowing, at which point the force carbonation is complete.
  7. Agitate the keg by rolling for about a minute, twice a day for the next 2 days. This ensures that everything is fully dissolved.
  8. Use the valve to release the built up pressure.
  9. Open the lid and stick an electric mixer into the keg. The mixer attachments should be about halfway submerged under the water. Set the mixer to the maximum power setting.
  10. Check the pH of the mineral concentrate every 5 minutes until it reaches a pH of 7.0-7.5. This process may take between 1 and 2 hours. Record the exact amount of time it took so you can just set a timer in the future.

Your hardness concentrate is now ready to use.

Brew Water Instructions

Prepare in a 1 liter bottle, or directly in your kettle.

  1. Add 50 mL (or 50 grams) Hardness.
  2. Add 0.50 mL (or 0.590 grams) Buffer.
  3. Fill remaining capacity with zero TDS water (about 949 grams).


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