Seventy-four inches long, 10 inches wide, 9 inches tall. The B515 is a keel-run tank: it lays 26 gallons down the centerline of a hull, in the dead space alongside stringers where no boxy tank could ever go. Low and centered is exactly where you want liquid ballast on a boat - full, this tank carries about 217 lb of water with almost no effect on trim height.
It is a B-series dual-role molding, so the same blank can be ordered as either a fresh water tank or a gray/black holding tank. In fresh service the polyethylene is FDA approved for potable water; in waste service the same wall handles holding duty. The role is set entirely by which fittings you have Ronco install and where - spin-welded or threaded, located to your marks. A tank this long especially rewards planning: print the drawing below and think about where the pickup should sit relative to bow rise before you mark it, then enter the layout in the on-page fitting planner.
The B515 ships at 86 lb, which tells you something about the molding: a 74-inch span needs real wall thickness to stay straight, and Ronco molds it heavy rather than letting it oil-can. Support it continuously along its length; a tank this shape should never bridge gaps in the hull structure. Built in Tustin, California by a shop that has molded marine tanks since 1974.
Compare the other long low shapes in our boat tank lineup, or start from the full range on the Ronco Plastics hub. Freight to your dock is quoted by ZIP in the freight estimator. OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics B515 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.
