a collapsible liquid storage tank for use in a freight container for selectively carrying solid freight and bulk liquid freight includes a substantially rigid gantry having a plurality of support posts , a first frame , a second frame suspended from the gantry , a substantially inelastic flexible fabric container having sidewalls connected between the first frame and the second frame , a water impermeable elastic bladder disposed within the fabric container , and a hoist coupled between the gantry and the second frame for lifting the second frame towards the first frame .