The CEN advanced wastewater treatment system from Fuji Clean USA (certified NSF 40/245) is an enhanced denitrification system modeled on the company’s standard CE system (NSF 40) achieving a total nitrogen removal rate of over 70 percent in NSF testing. With an integrated, inclusive septic tank and small footprint, the lightweight, fiber-reinforced plastic system fits tight, difficult-to-access sites. Contact-filtration treatment includes aerobic and anaerobic chambers with built-in flow equalization, continuous recirculation and controlled discharge, all powered by an efficient MAC linear diaphragm air blower that uses 1.27 kWh per day for most residential units. Models are available from standard three- to four-bedroomhomes to commercial-sized systems. 207/406-2927; www.fujicleanusa.com.