The retrofit Aerobic Remediator (ARU) from Aero-Stream is designed to help restore failed systems and provide simultaneous nitrification/denitrification. The diffuser is designed to lower TSS and BOD and can be installed through a 3-inch opening. The UL-listed device induces oxygen directly into septic tanks, turning passive anaerobic environments into active aerobic environments. After conversion, the microorganisms reduce the organic matter in the tank by 80 percent and suspended solids by 60 percent. The cleaner effluent reverses the aging process and eliminates the clogging biomat; within weeks systems are restored to full functionality, according to the manufacturer. 877/254-7093; www.aero-stream.com.