CeraPotta Ceramic Coffee Filter

The CeraPotta is a coffee filter made of porous ceramic: there’s no paper and no mesh, because the coffee drips through the walls of the cone itself. It’s made in Hasami, Nagasaki, a porcelain town in Japan, and sold by the Japanese design company h concept. The maker says its pores are about 5 micrometres wide, finer than a human hair, and that you can steer it towards a light or deep cup just by how you pour. It brews 1 to 4 cups at a time. Here’s how to use it, the maker’s recipe, and how to keep it from clogging.

The short version

• A paperless ceramic cone: coffee filters through the porous walls.
• Medium-coarse grind, about 30 g of coffee to 360 ml of water for two cups.
• 90 to 95°C water, a little hotter than usual, because it drains quickly.
• One pour to the rim for a light cup, or five pours for a deep one.
• Rinse with water only, and boil it when it starts to drip slowly.

What makes the CeraPotta different?

Most pour-over brewers hold a filter: paper in a V60, cloth in a cloth filter, or a steel mesh in a metal cone filter. The CeraPotta is the filter. Water passes through tiny pores in the fired ceramic, and the brew drips from the whole cone, while the grounds stay inside.

The maker says the ceramic holds back fine particles and “impurities”, and that this changes the taste. In its own test, a panel of three certified aqua sommeliers (Japan Aqua Sommelier Association) tasted tap water, mineral water and coffee with and without the filter. They reported coffee through the CeraPotta as softer, sweeter and better balanced, with good body, and coffee through paper as lighter and more bitter. That’s a small sensory panel run for the maker, so treat it as a description of the style rather than proof.

According to the maker, the forming, drying and firing are mostly done by hand, using techniques from Hasami porcelain, which has been made in Nagasaki for about 400 years, together with modern porous-ceramic technology. It also says that waste material from the factory is recycled into production.

What size is it?

	CeraPotta
Capacity	1 to 4 cups, with marks inside
Filter size	About 10 cm wide and 11 cm tall
Weight	Filter about 115 g; stand ring about 60 g
Fits	Cups or pots with an opening up to 8.5 cm across
Pores	About 5 µm (maker’s figure)

Sizes and weights are from Manufactum’s listing; the pore size is the maker’s.

How much coffee and water should I use?

The marks inside the cone are a coffee measure. The bottom mark is about 20 g, and each mark above it adds about 10 g.

Cups	Coffee	Marks from the bottom
1 to 2	About 20 to 30 g	1 to 2
3 to 4	About 40 to 50 g	3 to 4

The maker’s two-cup example uses about 30 g of coffee and about 360 ml of water, a ratio of about 1:12, on the strong side for pour-over. If that’s too strong for you, I’d add a little more water rather than grinding finer.

What grind and water temperature?

• Medium-coarse is the maker’s recommendation: a balanced cup, more coffee aroma, and less clogging.
• Coarse gives a cleaner, clearer cup.
• Never finer than medium, because fine grounds clog the pores.
• Water at 90 to 95°C. The maker suggests slightly hotter water than usual, because the CeraPotta drains faster than an ordinary filter.

How do you brew with a CeraPotta, step by step?

This is the maker’s two-cup method:

1. Rinse the empty filter with boiling water, and use that water to warm your cup or pot.
2. Add about 30 g of medium-coarse coffee.
3. Bloom: pour just enough water to wet all the coffee, and wait about 30 seconds.
4. Choose your pour (about 360 ml of water in all):
   • Light: pour slowly in circles, keep going up to the rim, and finish in a single pour. The weight of water pushes it through faster, for a light, refreshing cup.
   • Deep: pour in circles up to the fourth mark from the bottom, let it drop, and repeat five times. The slower extraction gives a deeper, fuller cup.
5. Rinse the filter with water when you’re done.

I’d start with the deep pour if you usually like a Kalita Wave or other pulse-poured cup, and the light pour if you prefer something closer to tea.

How do you clean and unclog it?

Day to day, rinse it with water only. The maker says not to use detergent: it can soak deep into the porous ceramic and spoil the taste of later brews. Rinsing with hot water before and after each use helps stop coffee oils building up.

When it drips slowly, or the coffee starts tasting sour, the pores are clogging. The maker’s routine:

Method	What to do
Boil	Cover the filter with water in a pan, opening facing up, and boil for about 10 minutes. Facing down, bubbles can float it.
Microwave	Cover it with water in a heatproof bowl and heat: about 5 minutes at 500 W or 2 minutes 30 seconds at 1,000 W.
Boost	Add bicarbonate of soda, about 2 tablespoons per litre of water.
Deep clean	If it’s still slow, soak it for about 6 hours in 40 to 60°C water with unscented sodium percarbonate (oxygen bleach) at the dose for tableware, rinse well, then boil for 10 minutes in fresh water.

After cleaning, let it cool and dry naturally. The maker warns that cooling it quickly under running water can crack it, and it shouldn’t go on a direct flame. If nothing works, the maker offers a paid maintenance service. Manufactum notes it’s not dishwasher safe.

General guidance only. Take care with boiling water and a hot ceramic filter, and follow the dose on any oxygen bleach.

What are the downsides?

• Price. Manufactum lists it at €84.90, far more than a plastic or ceramic cone for paper filters.
• It’s ceramic, so it can break if dropped, and the maker warns it can crack if cooled too fast.
• Maintenance. It needs boiling from time to time, and you can’t use soap.
• Grind limits. No fine grinds, so no espresso-fine experiments.

Who makes it?

The CeraPotta is sold by h concept (アッシュコンセプト), a Tokyo design company, and made in Hasami, Nagasaki. The maker lists two awards: the SCAJ New Product Award, Sustainable Product, 2023, from the Specialty Coffee Association of Japan, and a Red Dot design award in 2024. Coffee Bean Laboratory (コーヒー豆研究所), a Japanese coffee site, also notes the SCAJ award.

CeraPotta vs other methods

• Ceramic cone: a ceramic dripper that still uses a paper filter.
• Metal cone filter: another paperless option, with steel mesh and more oils in the cup.
• Cloth filter pour-over: reusable cloth, with a clean but full-bodied cup.
• V60: the classic paper cone, for comparison.

Explore every pour-over method in the pour-over chapter.