The WHISPER Biofilter from Evoqua Water Technologies is designed for quiet operation and effective odor treatment, removing 99 percent of incoming hydrogen sulfide. The rotating irrigation system provides uniform water and distribution for optimal biological conditions. The nondegradable Bioglas media, made from acid-resistant recycled glass, provides a long-lasting surface for biomass growth. The unit can treat airflows up to 1,100 cfm and hydrogen sulfide concentrations above 100 ppm. The units have skid-mounted controls for easy installation and operation. Regional service centers can provide turnkey full-service programs including on-site evaluation, installation, operation, service and performance reporting. Units are available on a monthly rental basis to reduce capital investment. 800/345-3982; www.evoqua.com.