Trickling filters are aerobic fixed-growth reactors that incorporate suspended media, promoting the growth of biomass. The name is derived from the process itself, which involves delivery of screened wastewater (or liquor) to the top of the media filter.

Concurrently, air is driven upward through the media. The biomass serves to both remove organic material and to remove ammonia by assimilation. Excess biomass drains out of the media chamber and into a secondary clarifier where it is separated and transferred to sludge disposal. ABCO supplies both rock and plastic media solutions. Plastic media is generally the preferred option, as it has fewer limitations in terms of weight, and can also provide a larger surface area per volume. Rock media can provide a higher degree of nitrate removal for low hydraulic loading systems, however is less efficient as the loading increases. ABCO is experienced in the design, installation and maintenance of effective wastewater sprinkler fields and offers this product as both a stand-alone installation and as a package deal with most water and wastewater treatment plants.