Activated sludge is one of the most widely used biological treatment methods for municipal and industrial wastewater. Activated sludge systems are scalable and can be fine-tuned for a variety of treatment goals, but they require significant infrastructure, skilled operators, and consistent energy input for aeration.

Bead filters, by contrast, are a more compact and modular treatment solution that combines mechanical and biological filtration. AST filters use small plastic beads that serve both as physical filtration media and as surfaces for microbial biofilm growth. As water passes through the tightly packed beads, suspended solids are trapped, and biofilm on the beads helps degrade dissolved organic matter. Bead filters offer a compact, efficient solution where space is limited and integrated mechanical-biological treatment is beneficial. The result is a simpler, lower cost solution with a smaller footprint.