Bio-Tab from Century Chemical Corp. is a tablet that sinks to the bottom of a septic tank where buildup problems begin. Its time-release technology is designed to gradually dissolve to create a growing area of activity at the bottom of the tank. There, self-reproducing bacteria and enzymes quickly grow as they digest and liquefy the organic waste. The tablet establishes itself by working from the inside out. Regular usage, combined with routine pumping, can help maintain a septic system in good working condition while also helping to keep the proper level of bacterial action established and reducing odors and gases, according to the maker. 800/348-3505; www.bio-tab.com.