How to Brew Coffee Using a Siphon (Vacuum Pot)

If you’ve ever watched a barista make coffee with a siphon and wondered how it works—or whether you could do it at home—this guide is for you. The siphon (or vacuum pot) isn’t just a dramatic brewing method; it’s a precise, full-immersion way to make clean, aromatic coffee without much effort once you know the steps.

To brew three cups of coffee using a Hario siphon, you’ll need 35g of freshly ground coffee (30g for the brew, 5g to pre-warm the upper chamber), heat the bottom chamber to around 90°C, and stir the slurry gently for 40–60 seconds after the water rises. The result? A balanced, smooth cup reminiscent of a light, sweet single origin.

What Is a Siphon Coffee Maker?

A siphon coffee maker—also called a vacuum pot—uses vapor pressure and vacuum suction to brew coffee. It consists of two glass chambers: a lower one that holds water and heats it, and an upper one where ground coffee brews. As the water heats, it rises into the upper chamber through a filter. When you remove or reduce the heat, a vacuum pulls the brewed coffee back down into the lower chamber, leaving the grounds behind. It’s equal parts science experiment and elegant brewer.

Why Use a Siphon? What’s the Result?

The siphon method is prized for producing clean, vibrant, and well-balanced coffee. Because it’s a full-immersion brew followed by filtration, it extracts flavors evenly and leaves behind most sediment. The result is often described as tea-like in clarity, with pronounced aromatics and a smooth mouthfeel. Many coffee enthusiasts appreciate how the method highlights the unique characteristics of single-origin beans without over-extraction bitterness or unwanted acidity.

How to Brew Coffee with a Hario Siphon (Step-by-Step)

This guide uses a Japanese Hario siphon, known for its durability and heat resistance. Here’s the exact process:

• Preheat your cups. Always prewarm your serving cups before brewing—that’s essential for maintaining temperature.
• Measure your coffee. For three cups, use 30g of freshly ground coffee (about 10g per cup), plus 5g extra to pre-warm the upper chamber. That’s a total of 35g.
• Add water to the lower chamber. Pour water into the bottom bulb to the 3-cup mark (enough for three servings).
• Assemble and start heating. Place the upper chamber on top of the lower one (without coffee yet), and heat the bottom chamber using a gas stove. Aim for a water temperature of around 90°C. A gas burner is ideal because you can control the flame easily.
• Attach the upper chamber. Once the water nears boiling (not quite there), attach the upper chamber. Then reduce the flame slightly and move it off-center to avoid scorching the coffee grounds later.
• Add coffee to the upper chamber. When the water rises into the upper chamber due to vapor pressure, turn off or lower the heat further, then add the 30g of ground coffee. (Do not add coffee before the water rises.)
• Stir the coffee slurry. Using a wooden stir stick, gently stir the coffee and water mixture for 40–60 seconds. Keep the stir gentle and avoid touching the bottom. Do not stir aggressively—it can make the coffee taste rough or astringent. For a stronger brew, stir a little longer.
• Trigger the draw-down. Immediately after stirring, use a damp cloth to gently wipe the bottom chamber’s rim or outer surface. This helps cool it slightly, triggering the vacuum effect. Watch as the brewed coffee is pulled back down into the lower chamber, leaving the grounds in the upper part.
• Serve. Your coffee is now ready to pour. Enjoy it black to experience its clarity, or add a touch of milk to enhance its natural chocolate and nutty undertones.

Note: In case your gas runs out mid-brew—as happened during the original demonstration—you can switch to an alcohol burner to finish the process.

Flavor Profile: What Does Siphon Coffee Taste Like?

The siphon-brewed coffee described in the original guide was made with a coffee resembling a Yemeni Mocha or perhaps a washed Ethiopian single origin. The result was a cup that was “not sour, not bitter,” with a “very prominent” flavor. The writer noted that adding milk brought out a smooth texture and hints of chocolate and nuts—possibly explaining why many commercial mochas include chocolate. Expect a clean, aromatic, and balanced profile with subtle sweetness and medium body.

Frequently Asked Questions

What temperature should the water reach in a siphon brew?

Heat the water in the lower chamber to around 90°C. You want it hot enough to create vapor pressure but not boiling aggressively when you add the coffee.

How much coffee do you use in a Hario siphon for three cups?

Use 30g of freshly ground coffee for the brew itself, plus 5g to pre-warm the upper chamber—totaling 35g for three cups. That’s roughly 10g per cup of actual brew.

How long should you stir the coffee in a siphon?

Stir the coffee and water mixture gently for 40–60 seconds after the water rises into the upper chamber. Avoid touching the bottom and stir softly to prevent harsh or gritty extraction.

Can you use any heat source for a siphon?

Yes, but a gas stove is ideal because you can adjust the flame precisely. You can also use an alcohol lamp if gas is unavailable, as demonstrated in the guide when the stove ran out of fuel.

Why does the coffee go back down into the lower chamber?

When you cool the lower chamber (by wiping it with a damp cloth), a vacuum forms and pulls the brewed coffee through the filter and back down into the bottom bulb, separating it from the grounds.

What kind of coffee tastes best in a siphon?

Light to medium roast single-origin coffees with distinct fruity, floral, or nutty profiles shine in a siphon. The method highlights clarity and subtle flavors, making it great for washed Ethiopians, Yirgacheffes, or balanced Latin American beans.

Recommended FrontStreet Coffee for Siphon Brewing

For siphon brewing, try FrontStreet Coffee’s Ethiopia Humbera—a washed Ethiopian single origin with bright acidity, floral notes, and a juicy body that shines through the siphon’s clarity. Also excellent is their Yirgacheffe offering, which delivers lemony brightness and stone fruit tones. For something deeper, their Brazil Queen Manor provides a sweet, nutty base that rounds out the cup beautifully. All three beans highlight the siphon’s ability to showcase origin character. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.