Abstract: A frame type container tank (1) comprises a tank (3) located within the framework (2). Fusto-conical bearer plates (25) mount the tank (3) to end frames (9) of the framework (2) and upper and lower longitudinal members (20, 21) join the end frames (9). Four reinforcing plate members (30) at the four lower corners of the framework (2) each comprise a pair of identical spaced apart parallel reinforcing plates (31) which extend between and are secured to the bearer plates (25) and the lower longitudinal members (21). Reinforcing struts (45) extend between the reinforcing plate members (30) and the lower longitudinal members (21). The provision of the reinforcing plate members (30) in combination with the reinforcing struts (45) provide for significant weight reduction in the framework (2) without loss in carrying capacity of the container tank (1).