A volume measurement apparatus is for a storage container and has an elongated member having a measurement scale marked thereon and an attachment mechanism configured to attach the elongated member onto a storage container. The storage container is capable of holding a liquid or granular substance. The volume measurement apparatus further has an adjustment mechanism configured such that a position and orientation of the elongated member can be adjusted relative to the storage container to align a minimum or maximum capacity marker on the measurement scale with a topmost level of the substance held in the storage container. The measurement scale is adapted such that it can be used to measure a volume of the substance held in the storage container.