bulk storage tanks intermediate bulk containers plastic tanks BULK STORAGE TANKS For more than 20 years, ACO has been recognized as one of the leading manufacturers of quality rotationally moulded products. ACO bulk storage tanks, moulded in premium grade linear or cross-linked polyethylene, provide a wide range of sizes and capacities to suit all applications. ACO bulk storage tanks, moulded products are made under a tough quality control standard to ensure that you get a reliable and consistent product. ACO double-wall bulk storage tanks possess great features which address all environmental and safety concerns. Double wall bulk storage tanks have a great self-supporting feature with a design made for space saving. You can also request your tank with an open-top outer containment configuration.