TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Component: The microorganisms include nitrosomas, nitrobacter, and/or heterotrophic bacteria.    TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Component: The waste treatment apparatus further comprises a collection mechanism for collecting a second treated waste from the second volume; an output mechanism for discharging the second treated waste following the treatment cycle; and a filtration mechanism provided within the apparatus for filtering the first treated waste and/or the second treated waste that has passed within and/or from the bioreactor. The waste treatment apparatus is configured to provide in each treatment cycle at least one relatively low-oxygen period and/or at least one relatively high-oxygen period. The bioreactor includes a recirculation mechanism for providing a recirculation circuit of the feed waste and/or the first treated waste and/or the second treated waste from and/or within the bioreactor to the feed tank and/or the first volume and/or the second volume. The recirculation mechanism is used for providing the recirculation circuit of the first treated waste within the bioreactor to the first volume. It is used for providing the recirculation circuit of the second treated waste from and/or within the bioreactor to the first or second volume. It is used for providing the recirculation circuit of the first treated waste and/or the second treated waste from and/or within the bioreactor to the feed tank. The volume of waste in the bioreactor is controlled by a combination of the recirculation and/or the addition of further feed waste by the feed tank. The substrate in the first volume is provided by packing, thus to give a first packed volume and provide surface area upon which microorganisms may reside and voids to allow passage of the first treated waste through. The packing includes segments of pipe, rubber, recycled rubber, Raschig and Lessing rings, and/or saddles. The waste treatment apparatus operates primarily on a liquids-rich stream. It is adapted to receive and treat a mixture of liquid and solid waste, where the mixture includes effluent from toilet discharge and/or an input volume bearing a relatively high organic load. The filtration mechanism is provided within the recirculation circuit such that a portion of the feed waste and/or the first treated waste and/or the second treated waste is filtered prior to discharging from the apparatus. It is provided within the bioreactor such that a portion of the feed waste and/or the first treated waste is filtered prior to discharging from the apparatus. It is provided in a fluid pathway distinct from the recirculation circuit. The apparatus is operably associable with the filtration mechanism provided downstream and/or upstream of the apparatus. The first packed volume is configured such that it filters the feed waste entering the first volume, thus to provide the first treated waste and/or provides support for the resident microorganisms. The collected second treated waste is split into the recirculation circuit and an exit pathway fluidly communicable with the output mechanism. The recirculation circuit returns a proportion of the second treated waste back to the first volume and/or the second volume for further treatment. The output mechanism discharges a proportion of the second treated waste from the bioreactor for optional later processing.Preferred Method: The step of recirculating waste includes untreated the feed waste and/or the first treated waste; or untreated the feed waste, the first treated waste and/or the second treated waste. The method further includes collecting the second treated waste from the second volume, where the second treated waste bears a relatively reduced organic load. The relative proportion of the relatively low-oxygen period(s) and the relatively high-oxygen period(s) occurring within the bioreactor is controlled by the quantity and rate of the feed waste to the first volume. Increased input of the feed waste provides for its increased aeration to provide a relatively high-oxygen period. The waste within the first volume is a combination of the feed waste and recirculated the first treated waste and/or recirculated the second treated waste. The first volume and/or the second volume may accommodate the relatively high-oxygen period(s) and/or the relatively low-oxygen period(s), thus to provide aerobic and/or anoxic waste treatments, respectively, in controllable rates and/or proportions. The first volume accommodates the relatively high-oxygen period(s). The second volume accommodates the relatively low-oxygen period(s). The feed waste and/or the first treated waste and/or the second treated waste are passed through the filtration mechanism. The resultant filtered second treated waste is suitable for purposes, e.g. surface irrigation or toilet flushing. Control of the rates of the recirculation and/or the feed waste alters the residence times and aeration of the waste in the first and second volumes, thus altering the aerobic: anoxic ratio of the treatment cycle. The selection of the relatively high-oxygen period(s) or relatively low-oxygen period(s) within the bioreactor provides effective control of nitrification and/or denitrification of the waste, respectively, within the bioreactor. Toggling the on/off period(s) of the recirculation and corresponding levels of oxygen within the second volume varies the degree of nitrification or denitrification in both the first and second volumes. Each relatively high-oxygen period has a relatively high rate of recirculation to provide a relatively greater proportion of relatively high-oxygen period(s). Each relatively low-oxygen period has relatively little or no recirculation to provide a relatively greater proportion of relatively low-oxygen period(s). The rate of nitrification within the bioreactor may also be controlled by the addition of one or more doses of the feed waste as desired or at predetermined points in the high-oxygen period(s) or the low-oxygen period/s. The efficiency of the bioreactor may be enhanced by adding to it one or more carbon-containing compounds, where the carbon-containing compounds include sugar(s), as desired or at predetermined points in the high-oxygen period(s) or the low-oxygen period(s).