April Flat Bottom Paper vs Sibarist WAVE (FAST / B3)

Fits

Flat basket, Kalita Wave 155, Kalita Wave 185

Flow

Fast · Manufacturer-stated

Material

Paper · Cellulose

Reuse

Single-use

Availability

Specialty only

How it brews

The Copenhagen roastery's own flat-bottom paper, sold Small (≈Kalita 155 / Origami S) and Large (size 175, for the April plastic brewer). It's cut to sit deep with a wide base and is marketed as flowing faster than conventional flat papers — that speed claim is April's, kept as a class rather than a number here. One honest ambiguity: older retailer copy described April filters as using Sibarist's abaca FAST technology, while the current listing says virgin wood pulp (cellulose); we record cellulose per the direct listing but don't treat abaca as confirmed. It drops into a Kalita Wave 155/185 seat, so it interchanges with those papers.

Fits

Kalita Wave 155, Kalita Wave 185

Flow

Fast · Manufacturer-stated

Material

Paper · Abaca

Reuse

Single-use

Availability

Specialty only

How it brews

Sibarist's abaca paper cut to the wave shape for Kalita-Wave beds, in S (155), M (185) and an L (8-12 cup) — offered in both the high-permeability FAST and the lower-porosity B3 grades. The wave geometry stands the bed on the fluted walls the way any Wave paper does, and it interchanges with Kalita-Wave papers of the matching size. Sibarist rates the FAST grade as fast-draining (its own claim, not measured here), the idea being you can grind finer for more extraction without choking the flat bed. Choose FAST for clarity and speed, B3 when you want more body and contact time on the same seat.