Abstract: An apparatus may include a float member and an output line. The float member is configured in contacting adjacency to first and second liquids contained in a container. The first liquid is less dense than the second liquid such that the first liquid floats on top of the second liquid. The float member may have a specific gravity selected responsive to the first and second liquids. When the second liquid is pulled from the container through the output line to a predetermined level, the float member occludes the output line. The specific gravity of the float member may be selected based on the fluid in the container previously, currently, or in the future, or some combination of the three. The specific gravity of the float member may be adjusted by changing material within the float member or changing the float member itself from a plurality of float members.

Abstract: In accordance with some embodiments, an apparatus may include a float member and retention member. The retention member is configured to retain the float member in fluid communication with at least one fluid in an interior of a container. The float member in a first position in relation to the retention member limits the at least one fluid from leaving the interior of the container, and the float member in a different, second position in relation to the retention member promotes the at least one fluid leaving the interior of the container. The retention member is in substantially the same relative position to the container in the first position and the second position.