The B531 stretches 71 gallons into a 63.25-inch-long molding about 23 inches wide and just 12.5 inches tall - proportions drawn for the underfloor of an RV or the long shallow tunnel of a boat's tank bay. Tanks like this ride between chassis rails or stringers, keep the weight low, and leave the living space alone.
Though most buyers run it as a fresh water tank, it is molded as a B-series dual-role blank: FDA-approved potable polyethylene with supply fittings in fresh service, or the identical molding with waste fittings as a long gray-water tank. Either way the fittings are installed by Ronco per order, spin-welded or threaded to the marks you supply. A 63.25-inch tank crosses a lot of frame members, so print the drawing below, mark ports where they will not fight the chassis, and finalize in the on-page fitting planner.
It ships at 111 lb - long spans demand heavy walls - and carries about 592 lb of water when full. Distribute that along the tank's length with cross-bearers rather than hanging it from two straps; long tanks fail at unsupported midpoints, not at the ends. Tustin, California production, continuous since 1974.
Other long-format moldings live in RV water tanks and boat tanks; the full catalog is on the Ronco Plastics hub. OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics B531 dimensional drawing - print it to plan your install and mark exactly where you want fittings located; Ronco installs spin-weld or threaded fittings to your marked spec.
