InSinkErator Bio-Charge 16-Ounce Replacement Cartridge # BIO-CG. Fits Septic Disposer and lasts 3 to 4 months with average use. Bio-ChargeŽ cartridge equals 4 bottles of other septic treatments. And Bio-ChargeŽ contains a citrus scent to help control odors from the sink and drain. There's also a surfactant to help break down soap and grease film that accumulates in drainpipes.