How to Use a Chemex

Chemex pour-over coffee maker being used to brew fresh specialty coffee showing the clean bright extraction method popular in Australian cafes

Seeing a Chemex on a cafe shelf in Melbourne or Sydney can be a bit intimidating. It looks more like a science experiment than a coffee maker. Once you know the basics, the Chemex produces an incredibly clean, sweet cup of coffee that highlights the fruity and floral notes typical of modern Australian roasts. Whether you are brewing for yourself or a table of mates at brunch, this guide will help you get the most out of your freshly roasted coffee beans.

The Quick Cheat Sheet

You do not need to be a scientist. Being close to these numbers is usually good enough. We use a 1:16 ratio (1 part coffee to 16 parts water), which works perfectly for most beans you will find in local roasteries.

Serves (Approx.) Water Required Coffee Beans Perfect For
1 mug (250ml) 250g 15–16g Just you
2 mugs (500ml) 500g 31–32g You and a mate
3 mugs (750ml) 750g 47–48g Small share house
4 mugs (1 litre) 1,000g 62–64g Sunday brunch or office pot

How to use a Chemex showing the equipment setup including bonded filters burr grinder digital scale and gooseneck kettle

What You Need

You do not need to spend a fortune. Apart from the Chemex itself, you likely have most of this in your kitchen already.

  • The Chemex: Any size, though the 6-cup is the standard found in most Aussie shops.
  • Filters: You must use bonded Chemex filters. Regular supermarket filters are too thin and will ruin the taste.
  • Grinder: A burr grinder is best (hand or electric).
  • Scales: Essential for consistency. A cheap digital kitchen scale works perfectly.
  • Kettle: Electric is fine. A gooseneck kettle is easier to pour, but not mandatory.
  • Timer: Your phone works a treat.

Step 1: Sort Your Beans and Grind

The Chemex shines with lighter roasts. Dark, oily espresso roasts can taste a bit ash-like in a filter brewer. Head to your local roaster and look for bags labelled filter roast, light or medium roast, or with flavour notes of citrus, stone fruit, berries, or floral.

The Grind

This is the most important variable. The texture should look like coarse sea salt or rough sand. It should be chunkier than espresso grind, but not as chunky as a French press.

  • Coffee tastes sour or thin? Grind finer next time.
  • Coffee tastes bitter or harsh? Grind coarser next time.

Freshly ground coffee at medium-coarse grind size for Chemex brewing showing the coarse sea salt texture required for clean pour-over extraction

Step 2: The Setup

  1. Boil your kettle: Let it sit for 30 to 40 seconds after boiling. You want it around 93 to 95°C.
  2. Fold the filter: Open the paper filter so that three layers are on one side and one layer is on the other.
  3. Place the filter: Put the three-layer side against the spout. This allows air to escape so the coffee flows smoothly.
  4. Rinse: Pour hot water through the empty filter. This warms the glass and removes that paper taste. Tip the water out before brewing.

Step 3: The Brew

The following steps use a two-mug example: 32g coffee and 500ml water.

1. The Bloom (Wake up the coffee)

Put your coffee in the filter and shake it to flatten the bed. Start your timer.

  • Pour about 60 to 70g of water (roughly double the weight of the coffee).
  • Make sure all grounds are wet.
  • Wait 30 to 40 seconds.
  • You will see bubbles and the coffee rising. This is CO2 escaping, which is essential for a smooth flavour.

2. The Main Pour

After the bloom finishes, pour the water slowly in circles, starting in the centre and spiralling out. Do not pour directly onto the paper walls. Try to get all the water (500g total) in by the 2:15 minute mark.

3. The Wait

Let it drain. The total time from start to finish should be between 3.5 and 4.5 minutes. If it drains in 2 minutes, your grind is too coarse. If it takes 6 minutes, your grind is too fine.

Chemex brew timeline showing the bloom first pour second pour and drawdown stages for a perfect two-mug pour-over

Brew Timeline Example (2 Mugs)

Step Action Timer
Bloom Pour 60–70g water 0:00 – 0:40
First pour Pour until scale reads 250g 0:40 – 1:20
Second pour Pour until scale reads 500g 1:20 – 2:15
Drawdown Wait for water to drain Finish ~3:30–4:00

Troubleshooting: How to Fix the Taste

Did it taste a bit off? Do not worry. Even the pros tweak their recipe.

If the coffee tastes… It is likely… Try this next time
Sour, sharp, lemony Under-extracted Grind finer or pour slower.
Bitter, dry, harsh Over-extracted Grind coarser or use cooler water.
Weak, watery Diluted Use less water (try a 1:15 ratio).
Muddy, not clean Clogged filter Use a coarser grind or ensure you are using proper Chemex filters.

Handy Tips for Australian Brewers

  • Water quality: In most Aussie capital cities, tap water is perfectly safe and soft enough for coffee. However, if you can smell chlorine or taste metal, run it through a standard filter jug first.
  • Summer iced coffee: For a clean iced coffee, use a tighter ratio (1:15), let it cool, and pour over ice.
  • Roast dates: Check the bag. Most local specialty roasters print the roasted on date. Try to use beans within 4 to 6 weeks of that date for the best flavour.
  • Ratio rule of thumb: For every 250ml cup of water, use roughly 15g of coffee.

Remove the filter, give the glass a swirl to mix the brew, and pour into your favourite mug.

The Chemex deserves exceptional beans.

Freshly roasted to order and delivered anywhere in Australia. Light and medium roasts perfect for filter brewing.

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