RDS Permanent/Below Deck Tanks

RDS Permanent Below Deck Fuel Tanks: Built for the Water

When your vessel's fuel system demands a reliable, long-term solution, RDS Manufacturing delivers with a lineup of permanent below deck fuel tanks engineered to meet the rigorous demands of marine environments. With roots going back to 1975, RDS has built a reputation as a leading manufacturer of premium aluminum fuel storage solutions for trucks, commercial equipment, and marine applications alike — and their below deck marine tanks represent some of the most carefully engineered products in the category.

5052 Aluminum Alloy Construction

The foundation of every RDS below deck tank is 5052 aluminum alloy — a marine-grade material chosen specifically for its strength-to-weight ratio and resistance to corrosion in the harsh, salt-laden environment found on and near open water. Unlike steel tanks that can rust from the inside out and contaminate fuel systems over time, RDS aluminum tanks are built to last the life of the vessel. Each tank also features radius-bent corners rather than fully welded corner joints on select models, reducing potential stress points in the hull.

US Coast Guard and NMMA Certified

Every RDS permanent below deck tank is manufactured and tested to US Coast Guard and NMMA (National Marine Manufacturers Association) standards — the two most critical benchmarks in recreational marine safety. Each unit is 100% pressure tested to verify its ability to retain pressure and withstand the constant motion, impact, and vibration inherent to boating. Before welding, all aluminum components are treated to eliminate contamination that could weaken welds or create leak points — a level of quality control that speaks to RDS's commitment to safety at sea.

Multiple Configurations for Any Hull

RDS recognizes that no two hulls are exactly alike. Their below deck tank lineup spans a range of shapes and capacities designed to fit the space constraints of real-world boat builds. Available configurations include rectangular, belly-shaped, port-side, and starboard-side profiles, with capacities typically ranging from 12 to 55 gallons. Whether you're replacing an aging tank on a center console or fitting a larger cruiser, there's an RDS option designed to integrate cleanly into your existing fuel system.

Ready-to-Install Features

RDS doesn't just deliver a tank — they deliver a system. Each below deck unit comes equipped with electrical sending units for accurate fuel level monitoring at the helm, along with removable vent plugs and pre-installed mounting brackets for secure installation. Standard fittings typically include a 1/4" NPT pickup, 1-1/2" fill, and vent connections, making integration with existing fuel lines straightforward. Many models are compatible with both gasoline and diesel, adding to their versatility across different powerplant configurations.

For boaters who demand a permanent fuel solution that meets the highest regulatory standards without sacrificing fitment flexibility, RDS permanent below deck tanks are a proven, trusted choice. Explore the full Permanent/Below Deck Tanks category or visit the complete RDS Manufacturing brand page to see everything they offer.