Eighteen gallons of fresh water is a long weekend for two people if the galley is disciplined. The B104 is the tank for that math: a marine water molding in FDA-compliant potable polyethylene, shipped as a clean blank with no fittings installed until you place them. It suits the refit where the old tank came out crumbling and the new one has to enter through a locker opening the old one never saw.
At 24 lb empty it is a one-person carry down the companionway. Full, plan for about 150 lb - water is 8.34 lb per gallon and it never gets lighter - so give it a shelf that bears the whole bottom and strap it against the seaway.
The fitting workflow is Ronco's standard, run the same way in Tustin, California since 1974: print the drawing below, mark where the fill, feed, and vent should land, or drop them on the on-page fitting planner, and the plant spin-welds or thread-installs to your marks. The same blank can also be ordered for waste duty if your boat needs a holding tank in this envelope. Related sizes are in boat tanks and across the Ronco Plastics hub. OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics B104 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.
