The Ronco Plastics B181 spreads 20 gallons across 30 x 18 x 10.5 inches - a low, wide molding built for the horizontal gaps under berths, seats, and camper floors. It is part of Ronco's marine water / waste series, which makes it two catalog entries in one shell: ordered with potable fittings it is a fresh water tank in FDA-compliant polyethylene; ordered with waste fittings it is a 20 gallon gray or black holding tank mounted right where a holding tank works best, at the bottom of the system.
Shallow tanks demand exact ports, and exact ports are the Ronco method: fittings installed per order, spin-welded or threaded at your marked positions. With only 10.5 inches of height, outlet placement at the true low corner is the difference between a tank that drains and a tank that keeps a permanent puddle. Print the dimensioned drawing below, mark it against your floor's actual slope, and set the layout in the fitting planner on this page.
The shell ships at 25 lb and holds about 167 lb of water when full, distributed gently across the wide base - continuous support underneath and a strap over the top finishes the job. Molded in Tustin, California since 1974. Low-profile alternatives are at boat tanks and RV water tanks, the whole family at the Ronco Plastics hub. OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics B181 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.
