Bolted steel tanks from Superior Tank are available with steel roofs as well as open-top configurations, and can be used as storage tanks, clarifiers and anaerobic digesters. They are delivered directly to the job site as complete kits. Steel panels and other main components are prefabricated, including factory-applied powder coat or hot-dipped galvanized finish. Tanks range in size from 4,000 to 3.5 million gallons, and are designed with a variety of industry standards, including AWWA, NFPA and FM approvals. Several powder-coating formulas are available, including variations for potable water and corrosive wastewater. 888/499-8109; www.superiortank.com.