The Retro-Air Rejuvenator System from Septic Services can be used in new or existing septic systems and installed in single or multiple compartment septic tanks. It is designed to eliminate clogged drainfield biomat as well as other secondary treatment systems, and is recommended by the maker in aeration systems that are prone to backup. It is designed to aerobically restore failed anaerobic installations or prevent failures in new systems by delivering a constant flow of air to the diffuser. Over time, aerobic bacteria consume the biomat, allowing the soil to absorb effluent once again. It is designed for quick and easy installation and requires minimal maintenance. 800/536-5564; www.retro-air.com.