A buoy or float can be positioned within a separation container to assist in a physical separation of components of a whole material positioned in the separation container. The buoy can be positioned within the container to move from between and separation a first end and a second end of the container substantially unaffected by a portion of the whole material, including a clotted portion thereof. A first port can be provided near the first end of the container for introduction of the whole material and a second port can be provided near the second end of the container for removal of at least a portion of a separated material.