At a 22 lb ship weight, the Ronco Plastics B167 is an 18 gallon fresh water tank you can carry aboard under one arm - and 18 gallons is more capability than it sounds: a weekend of drinking, cooking, and washing for a small crew, or a permanent step up from jerry cans on a pocket cruiser. The molding is FDA-compliant polyethylene, one piece, no seams, from Ronco's Tustin, California plant, in the marine tank business since 1974.
Like its larger siblings, the B167 is completed to order: fittings spin-welded or threaded at the locations and sizes you mark. Small boats have the least forgiving plumbing runs, so this matters - the fill has to meet a short hose from the deck plate, the vent has to clear the waterline logic of a small hull, and the pickup has to sit where an 18 gallon tank actually empties. Print the drawing below, mark it, and confirm through the fitting planner on this page.
Full, it carries about 150 lb of water. Strap it as if the boat will be dropped off a wave, because eventually it will be. Sizes up and down from here live at boat tanks; the whole Ronco family is at the Ronco Plastics hub; ZIP-level shipping comes from the freight estimator. OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics B167 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.