How do I make a pour over with a thin filter?

The thickness of your paper filter is a critical, often overlooked variable in your coffee brewing guide. A thin filter allows for a higher flow rate, meaning water passes through the coffee bed faster than it would with a thicker, more dense paper. If you do not adjust your technique, this rapid flow often results in a cup that tastes sour, thin, or lacking in sweetness—classic signs of under-extraction.

To master a pour over with a thin filter, your primary adjustment should be the grind size. Because the filter offers less resistance, you need to create that resistance within the coffee bed itself. Try grinding your beans slightly finer than you would for a standard filter. This increases the surface area of the grounds and slows the water's path, allowing for more thorough extraction of the coffee's soluble compounds.

Your pouring technique also becomes more important with high-flow equipment. With a thin filter, you may find that the water drains away before you have finished your pour. Focus on a slow, steady stream from your kettle. If you are using a gooseneck kettle, maintain a consistent height and flow rate to ensure the grounds are evenly saturated. If the water level drops too quickly, you might need to adjust your pouring intervals to keep the bed submerged for the desired contact time.

In practice, treat the thin filter as a tool that gives you more control over the extraction speed. If your coffee still tastes weak, continue to refine your grind size until you reach the desired balance of acidity and sweetness. Conversely, if the coffee becomes bitter or astringent, your grind may be too fine, causing the water to stall. By adjusting these variables, you can achieve a clean, vibrant cup that highlights the unique characteristics of your single-origin beans.