The Bio-Pure is a two chamber unit and consists of a conical tank, with an inner circular aeration chamber inside, which is open at the base. The space between the inner and outer tank is the clarifier chamber.  The draft tube is positioned 100 mm from the base of the clarifier, extends up into the aeration chamber.  Air from the compressor housed under the lid is piped to a diffuser in the draft tube.  Raw sewage enters the aeration chamber through the inlet pipe, flowing into the centre of the chamber.  Air surging up from the draft tube aerates the sewage, causing an aerobic bacterial colony to establish and digest the organic matter.

As more raw sewage enters the chamber through the inlet pipe, an equal amount of effluent displaces through the open bottom into the clarifier (outer tank).  The quiet conditions in the clarifier allow all the suspended solids to sink to the base of the clarifier and they are drawn back up the draft tube by the upward flow of air for further digestion in the aeration chamber.  The clear effluent rises to the top of the clarifier and passes over a weir into the outlet pipe and is disposed of through a water course or soak away.  The Bio-Pure constantly recycles the sewage via gravity and achieves nearly total solids digestion.  Most sewage treatment units consist of three chambers, the first one being a Primary Settlement Tank where the solids form a septic sludge.  They require regular emptying by tanker.  Because the Bio-Pure digests the solids as well as the organic matter in the liquid, the unit has a much longer emptying interval than any three stage unit.  The interval is 3 to 5 years.