provided is a “ parts washer ” that includes a fluid that performs a cleaning function and maintains the viability of microorganisms in the fluid which biodegrade organic material in contact with a biological component , the parts . “ parts ” include objects befouled with organic material and / or particulate matter . the cleaning fluid includes a surfactant that functions to separate organic waste from the parts being washed . a multi - tiered basin houses the cleaning fluid and the biological component living within the fluid that breaks down organic wastes produced by the cleaning fluid . the multi - tiered basin which forms the mechanical component of the washer , includes a sink member with a false bottom , and a support grid and filter to support microorganisms interposed between the false bottom and a bottom panel of the sink member . the tank is partially filled with the cleaning fluid and a pump and conduit assembly directs a flow of the cleaning fluid to the basin and aerates the cleaning fluid . recirculation is facilitated by discharge of the cleaning fluid into the basin to flow through a drain hole in the false bottom , through the filter and support grid , and then through a drain hole in the bottom panel of the sink member back into the tank for reuse . a heater , thermostat , and a level control assembly function to maintain the cleaning fluid within a certain temperature range so as to maintain a proper environment for the microorganisms .