An improved compost bin for the effective decomposition of a volume of compostable matter such as food waste, has many vertical bin walls which surround a base and define a bin which contains compostable matter comprises: (a) many apertures formed into vertical bin walls; (b) many hollow ventilation tubes each having an interior end and an open exterior end, extending through one of many apertures so that the open end remains exterior to the bin, while the interior end and the majority of the length is contained within the bin in contact with the compostable matter contained within the bin, where the portion of the hollow tube in the compost bin has many perforations on it so as to ensure proper aeration for the bin to permit efficient decomposition; and (c) a cross-tube connecting the open exterior ends of the hollow ventilation tubes and possessing a down turned segment extending perpendicular to the ground and terminating at an open cross-tube end, where both the down turned and open ends permit air to travel through to reach the compostable matter, but preventing any odourous gases from escaping from within the bin interior. The bin preferably has a bio-filter bag comprising a porous material, filled with organic matter secured to the open cross-tube, allowing any gases that escape to be filtered. The bin is preferably constructed from four vertical bin walls such that the interior is equal to a volume of one cubic yard, and such that the length of the walls assures uniform heat distribution throughout the bin. The front vertical bin walls are preferably removable to allow withdrawal of finished compost, and are rearrangable to accomodate different recipes of compostable material.    USE -   The bin is used for the decomposition of household and animal waste.    ADVANTAGE -   The bin prevent the release of odourous unfiltered gases such as ammonia escaping from the bin during composting. As the bin comprises interchangeable and removable panel walls, the finished compost can be removed easily, and different aeration and ventilation arrays can be set up to produce different recipes of compost.