Minerals · Pre-registration open
Water, made on purpose.
Light roasts give their best with soft, low-buffer water. You can make it at home from distilled water and two food-grade minerals. Below are exact recipes, a calculator, and the kit we’re developing to make it effortless.
Ultralight Mineral Kit
Two pre-weighed sachets, one magnesium for hardness and one bicarbonate for buffer. Each makes a 1 L concentrate with distilled water. A recipe card covers the classics and our ultra-light starting point.
- Food-grade magnesium sulfate (Epsom salt) and potassium bicarbonate
- Dose for 1 L concentrates at 1000 ppm (as CaCO₃)
- Works with every recipe on this page
Price and availability to be announced. Pre-register and we’ll tell you first. No payment is taken.
Pre-registerStep 1
Make two concentrates
This is the two-concentrate method published by Barista Hustle. Each concentrate is made so that 1 g of concentrate in 1 L of finished water adds 1 ppm of hardness (GH) or alkalinity (KH), measured as CaCO₃.
Magnesium concentrate
2.45 g
Epsom salt (magnesium sulfate heptahydrate, MgSO₄·7H₂O) dissolved in 1 L distilled or deionised water gives 1000 ppm GH as CaCO₃.
Only if you have true anhydrous MgSO₄ (lab grade, rare): use 1.20 g instead.
Bicarbonate concentrate
1.68 g
Sodium bicarbonate (baking soda, NaHCO₃, not baking powder) dissolved in 1 L distilled or deionised water gives about 1000 ppm KH as CaCO₃.
Prefer potassium? Use 2.00 g potassium bicarbonate (KHCO₃) for the same 1000 ppm KH. Same chemistry, by molar mass.
You’ll need a scale that reads to 0.01 g, and clean, odour-free bottles. Label them clearly.
Step 2
Mix your brewing water
For 1 L of brewing water, weigh the concentrates into a clean bottle and top up with distilled water to the amount shown. Scale everything for larger batches.
| Recipe | Magnesium conc. (g) | Bicarbonate conc. (g) | Distilled water (g) | GH / KH (ppm) |
|---|---|---|---|---|
| Melbourne-style Very soft. Good for long brews and cuppings. | 23.7 | 11.5 | 964.8 | 24 / 12 |
| WOC Budapest World Brewers Cup Budapest target range. | 51.2 | 40.1 | 908.7 | 51 / 40 |
| SCA SCA (SCAA 2009 handbook) target values. | 68.6 | 40.1 | 891.3 | 69 / 40 |
| Barista Hustle BH’s original recipe and a balanced all-rounder. | 80.7 | 40.1 | 879.2 | 81 / 40 |
| Rao Close to Scott Rao’s recommended chemistry. | 75.7 | 50.1 | 874.2 | 76 / 50 |
| Hendon Near the centre of Hendon and Colonna-Dashwood’s “ideal brew zone”. | 99.9 | 30.8 | 869.3 | 100 / 31 |
| Ultralight starting point Our suggestion for very light roasts. Low buffer keeps acidity vivid. Not a published standard; tune it to taste. | 50.0 | 15.0 | 935.0 | 50 / 15 |
Recipes 1–6 as published by Barista Hustle in “Barista Water Recipes” (2019). Source: baristahustle.com. Rule of thumb from the same source: if a coffee tastes too sharp, try a little more buffer. KH above about 70 ppm tends to mute most coffees.
Calculator
Any target, any volume
Pick a preset or enter your own GH and KH. Assumes distilled or deionised base water and the concentrates above.
Buffer concentrate: 1.68 g sodium bicarbonate per litre. Magnesium concentrate: 2.45 g Epsom salt per litre.
Weigh into your bottle
Equivalent dry minerals for the whole batch, if dosing directly: – Epsom salt and – sodium bicarbonate. Amounts this small need a 0.001 g scale, which is why concentrates are easier.
Use food-grade minerals
Buy food-grade Epsom salt and bicarbonate, unscented, with no additives. Start from distilled, deionised or pure RO water you’ve checked.
Kettle, not espresso machine
These magnesium-only recipes contain no calcium. Barista Hustle advises against using them in espresso machines because of possible corrosion. Use them for filter brewing.
Storage
Keep concentrates in clean, sealed, dark bottles in the fridge and use them within about a month (around a week at room temperature). Throw them out if they turn cloudy or smell off.