The AeroPress is already one of the most versatile coffee makers around, but a growing ecosystem of accessories promises to make it even better. The Fellow Prismo is one of the most popular — a pressure-actuated valve attachment that claims to produce espresso-style coffee with crema, all while eliminating the need for the inverted brewing method. At around $25 (or 20 pounds), is it worth adding to your setup? We put it through a blind taste test to find out.
What Is the Fellow Prismo?
The Prismo is a two-part attachment that replaces the standard filter cap on your AeroPress:
- The valve — a pressure-actuated cap that clips onto the bottom of your AeroPress, creating a no-drip seal that lets coffee steep without filtering through prematurely.
- A metal filter — etched with the Fellow logo, it sits inside the valve with a rubber seal. This eliminates the need for paper filters entirely.
The idea is that the valve builds up pressure during the plunge, creating espresso-style extraction with crema. Fellow also says it can be used for full-immersion cold brews, iced teas, and more. The no-drip seal is particularly appealing because it removes the need for the inverted AeroPress method — no more risky flipping.
The Blind Taste Test
To keep things honest, we set up a blind comparison using Taylor’s Lazy Sunday ground coffee across three methods:
- Standard AeroPress (right-side up)
- Inverted AeroPress method
- AeroPress with Fellow Prismo
A partner brewed all three and placed them in unmarked cups. Here’s how they ranked:
First Place: Inverted AeroPress Method
Lovely balance with really nice texture. The perfect combination of chocolate, fruit — not too smoky, not too sharp. It had the benefit of a full minute of steeping after stirring, which let the flavors develop beautifully.
Second Place: Standard AeroPress
Nice, mellow, and smooth. Really strong color throughout with no wateriness. Not overpowering — a pleasant, easy-drinking espresso with dark fruit and cranberry notes.
Third Place: Fellow Prismo
Unfortunately, the Prismo came in last. The cup was quite strong but didn’t deliver much flavor complexity. It was bitter, slightly vinegary, and had a rough, grainy texture — possibly from sediment getting through the metal filter. It seemed to pull the worst parts of the flavor spectrum without the fruit sweetness or rich chocolate that the other methods produced.
The Cleanup Problem
One of the AeroPress’s greatest strengths is how easy it is to clean up — pop off the cap, push out the puck, rinse, done. The Prismo significantly complicates this. The coffee puck doesn’t come away from the metal filter easily, and any accessory that takes away from the AeroPress’s signature cleanup simplicity is a real drawback.
What the Prismo Gets Right
The no-drip seal is genuinely useful. The most cumbersome part of the inverted AeroPress method is the mess risk — it can go wrong, it can explode, it can be chaotic. The Prismo holds everything in place until you’re ready to plunge. It feels like the solution the AeroPress’s inventor would have preferred over people flipping the device upside down.
The included metal filter is also a nice bonus. Metal filters on their own can be pricey, so the Prismo is a decent way to get both an accessory and a reusable filter in one package.
Our Verdict
The Fellow Prismo is a fun accessory, and the no-drip seal addresses a real pain point. But in our blind taste test, the coffee it produced ranked behind both standard and inverted AeroPress methods. The recommended recipe (20 grams of coffee, 50ml of water) may need tweaking — that’s an intense ratio, especially under pressure. With some experimentation on measurements, the results might improve.
If you’re curious, give it a try. But if you’re already comfortable with the inverted method, the Prismo may not offer enough of an upgrade to justify the purchase.
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