Marine and RV Water and Holding Tanks for Sale

Pick the size, the shape, and the fitting locations to make a perfect fit for your Marine or RV Water and Holding Tank replacement.   You won’t find better-made RV or Marine holding tanks for the price.

Made from one piece to form 3/8"; thick walls using a roto-mold process to create a seamless holding tank superior in strength and performance. The bottom line: These tanks are nearly unbreakable and are built to go the distance, at sea or on the road.

Fittings: You customize the placement of the fittings when you place the order. We spin-weld the fittings to ensure your holding tank is securely connected to your plumbing.

  • Complies with NSF 61, FDA Reg CFR 177.1520, and Coast Guard Standards
  • Made from virgin polyethylene (poly) resins
  • Seamless tank made from one piece (less likely to break or leak)
  • 3/8” thick tank walls
  • Customized fitting placement
  • Spin weld fittings
  • Outlasts the competition

For use as RV freshwater tanks, RV holding tanks, RV black water holding tanks, RV waste holding tanks, Marine fresh water tanks, Marine holding tanks, and more!

We have 100's of sizes ranging from 2 gallons, 40 gallons, 50 gallons, 100 gallons, up to 250 gallons for these marine and rv fresh water and holding tanks.

  • Marine Holding Tanks
  • Marine Water Tanks
  • RV holding Tanks
  • RV Water Tanks
  • RV Black Water Tanks

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RV & Marine Tanks

  • 57 Gallon RV Holding Tank H-642. Technical drawing of a polyethylene holding tank designed for your rv and camper.

    57 Gallon RV Holding Tank H-642

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 57 Gallon RV Holding Tank, Part# H-642, is engineered to meet the requirements of mobile...

    MSRP: $453.58
    $431.25
    Add to Cart
  • 57 Gallon RV Holding Tank H-377 [OR] . Technical drawing of a polyethylene holding tank designed for your rv and camper.

    57 Gallon RV Holding Tank H-377 [OR]

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 57 Gallon RV Holding Tank, Part# H-377 [OR], is engineered to meet the requirements of mobile...

    MSRP: $388.79
    $369.65
    Add to Cart
  • 57 Gallon RV Holding Tank H-349 . Technical drawing of a polyethylene holding tank designed for your rv and camper.

    57 Gallon RV Holding Tank H-349

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 57 Gallon RV Holding Tank, Part# H-349, is engineered to meet the requirements of mobile...

    MSRP: $349.91
    $332.68
    Add to Cart
  • 57 Gallon RV Holding Tank H-283 [OR] . Technical drawing of a polyethylene holding tank designed for your rv and camper.

    57 Gallon RV Holding Tank H-283 [OR]

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 57 Gallon RV Holding Tank, Part# H-283 [OR], is engineered to meet the requirements of mobile...

    MSRP: $311.03
    $295.72
    Add to Cart
  • An image of a 49 Gallon Marine Fresh Water Tank | B482

    58 Gallon RV Fresh Water Tank | RV63W

    This 58-gallon Ronco RV fresh water tank (RV63W) provides reliable potable water storage for recreational vehicles. Measuring 42" x 23" x 15 1/2", it is sized to fit a range of RV builds and offers dependable water capacity for trips of all lengths...

    $475.01
    Add to Cart
  • An image of a 41 Gallon Marine Fresh Water Tank | B453

    58 Gallon RV Fresh Water Tank | RV60W

    This 58-gallon Ronco RV fresh water tank (RV60W) provides reliable potable water storage for recreational vehicles. Measuring 44" x 22" x 15 1/2", it is sized to fit a range of RV builds and offers dependable water capacity for trips of all lengths...

    $475.01
    Add to Cart
  • An image of a 15 Gallon RV Fresh Water Tank | RVB251

    58 Gallon RV Fresh Water Tank | RV44W

    This 58-gallon Ronco RV fresh water tank (RV44W) provides reliable potable water storage for recreational vehicles. Measuring 34" x 34" x 13", it is sized to fit a range of RV builds and offers dependable water capacity for trips of all lengths...

    $475.01
    Add to Cart
  • An image of a 21 Gallon Marine Fresh Water Tank | B396

    58 Gallon RV Fresh Water Tank | RV43W

    This 58-gallon Ronco RV fresh water tank (RV43W) provides reliable potable water storage for recreational vehicles. Measuring 58" x 20" x 13", it is sized to fit a range of RV builds and offers dependable water capacity for trips of all lengths...

    $475.01
    Add to Cart
  • An image of a 135 Gallon RV Fresh Water Tank | B407

    58 Gallon RV Fresh Water Tank | RV42W

    This 58-gallon Ronco RV fresh water tank (RV42W) provides reliable potable water storage for recreational vehicles. Measuring 46 3/4" x 20 3/4" x 15 1/2", it is sized to fit a range of RV builds and offers dependable water capacity for trips of all...

    $475.01
    Add to Cart
  • An image of a 49 Gallon Marine Holding Tank | B482

    58 Gallon Marine Fresh Water Tank | BOAT63W

    This 58-gallon Ronco marine fresh water tank (BOAT63W) is built for onboard potable water storage on boats and watercraft. Measuring 42" x 23" x 15 1/2", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended trips...

    $480.02
    Add to Cart
  • An image of a 30 Gallon Marine Fresh Water Tank | B481

    58 Gallon Marine Holding Tank | BOAT63W

    This 58-gallon Ronco marine holding tank (BOAT63W) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 42" x 23" x 15 1/2", it is designed to fit common marine compartment layouts while providing dependable...

    $480.02
    Add to Cart
  • An image of a 41 Gallon Marine Holding Tank | B453

    58 Gallon Marine Fresh Water Tank | BOAT60W

    This 58-gallon Ronco marine fresh water tank (BOAT60W) is built for onboard potable water storage on boats and watercraft. Measuring 44" x 22" x 15 1/2", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended trips...

    $480.02
    Add to Cart
  • An image of a 45 Gallon Marine Fresh Water Tank | B452

    58 Gallon Marine Holding Tank | BOAT60W

    This 58-gallon Ronco marine holding tank (BOAT60W) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 44" x 22" x 15 1/2", it is designed to fit common marine compartment layouts while providing dependable...

    $480.02
    Add to Cart
  • An image of a 25 Gallon RV Fresh Water Tank | RVB250

    58 Gallon Marine Fresh Water Tank | BOAT44W

    This 58-gallon Ronco marine fresh water tank (BOAT44W) is built for onboard potable water storage on boats and watercraft. Measuring 34" x 34" x 13", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended trips on...

    $480.02
    Add to Cart
  • An image of a 14 Gallon RV Fresh Water Tank | RVB245

    58 Gallon Marine Holding Tank | BOAT44W

    This 58-gallon Ronco marine holding tank (BOAT44W) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 34" x 34" x 13", it is designed to fit common marine compartment layouts while providing dependable waste...

    $480.02
    Add to Cart
  • An image of a 21 Gallon Marine Holding Tank | B396

    58 Gallon Marine Fresh Water Tank | BOAT43W

    This 58-gallon Ronco marine fresh water tank (BOAT43W) is built for onboard potable water storage on boats and watercraft. Measuring 58" x 20" x 13", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended trips on...

    $515.18
    Add to Cart
  • An image of a 7 Gallon Marine Fresh Water Tank | B395

    58 Gallon Marine Holding Tank | BOAT43W

    This 58-gallon Ronco marine holding tank (BOAT43W) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 58" x 20" x 13", it is designed to fit common marine compartment layouts while providing dependable waste...

    $515.18
    Add to Cart
  • An image of a 135 Gallon Marine Fresh Water Tank | B407

    58 Gallon Marine Fresh Water Tank | BOAT42W

    This 58-gallon Ronco marine fresh water tank (BOAT42W) is built for onboard potable water storage on boats and watercraft. Measuring 46 3/4" x 20 3/4" x 15 1/2", it fits a wide range of vessel layouts and provides reliable fresh water capacity for...

    $480.02
    Add to Cart
  • An image of a 135 Gallon Marine Holding Tank | B407

    58 Gallon Marine Holding Tank | BOAT42W

    This 58-gallon Ronco marine holding tank (BOAT42W) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 46 3/4" x 20 3/4" x 15 1/2", it is designed to fit common marine compartment layouts while providing...

    $480.02
    Add to Cart
  • 58 Gallon RV Water Tank W-486. Technical drawing of a polyethylene water tank designed for your rv.

    58 Gallon RV Water Tank W-486

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 58 Gallon RV Water Tank, Part# W-486, is engineered to meet the requirements of mobile water...

    MSRP: $336.95
    $320.36
    Add to Cart
  • 58 Gallon Marine Water Tank MW-486. Technical drawing of a polyethylene water tank designed for marine vessels.

    58 Gallon Marine Water Tank MW-486

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 58 Gallon Marine Water Tank, Part# MW-486, is engineered to meet the requirements of mobile...

    MSRP: $554.76
    $527.44
    Add to Cart
  • 59 Gallon Marine Water Tank MW-76. Technical drawing of a polyethylene water tank designed for marine vessels.

    59 Gallon Marine Water Tank MW-76

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 59 Gallon Marine Water Tank, Part# MW-76, is engineered to meet the requirements of mobile...

    MSRP: $448.22
    $426.15
    Add to Cart
  • 59 Gallon Marine Water Tank MW-494. Technical drawing of a polyethylene water tank designed for marine vessels.

    59 Gallon Marine Water Tank MW-494

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 59 Gallon Marine Water Tank, Part# MW-494, is engineered to meet the requirements of mobile...

    MSRP: $773.73
    $735.64
    Add to Cart
  • 59 Gallon RV Holding Tank H-645. Technical drawing of a polyethylene holding tank designed for your rv and camper.

    59 Gallon RV Holding Tank H-645

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 59 Gallon RV Holding Tank, Part# H-645, is engineered to meet the requirements of mobile...

    MSRP: $362.87
    $345.01
    Add to Cart
  • 59 Gallon RV Holding Tank H-442[OR] . Technical drawing of a polyethylene holding tank designed for your rv and camper.

    59 Gallon RV Holding Tank H-442[OR]

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 59 Gallon RV Holding Tank, Part# H-442[OR], is engineered to meet the requirements of mobile...

    MSRP: $362.87
    $345.01
    Add to Cart
  • 59 Gallon RV Holding Tank H-441 [OR] . Technical drawing of a polyethylene holding tank designed for your rv and camper.

    59 Gallon RV Holding Tank H-441 [OR]

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 59 Gallon RV Holding Tank, Part# H-441 [OR], is engineered to meet the requirements of mobile...

    MSRP: $362.87
    $345.01
    Add to Cart
  • 59 Gallon RV Holding Tank H-281 [OR] . Technical drawing of a polyethylene holding tank designed for your rv and camper.

    59 Gallon RV Holding Tank H-281 [OR]

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 59 Gallon RV Holding Tank, Part# H-281 [OR], is engineered to meet the requirements of mobile...

    MSRP: $311.03
    $295.72
    Add to Cart
  • An image of a 25 Gallon RV Fresh Water Tank | RVB163

    60 Gallon RV Holding Tank | RV82H

    This 60-gallon Ronco RV holding tank (RV82H) is designed for blackwater and greywater waste storage in recreational vehicles. Measuring 50" x 33" x 10", it fits common RV underbelly and compartment configurations while providing reliable waste...

    $492.07
    Add to Cart
  • An image of a 26 Gallon RV Holding Tank | RV62H

    60 Gallon RV Fresh Water Tank | RV54W

    This 60-gallon Ronco RV fresh water tank (RV54W) provides reliable potable water storage for recreational vehicles. Measuring 36" x 30" x 14 1/4", it is sized to fit a range of RV builds and offers dependable water capacity for trips of all lengths...

    $500.11
    Add to Cart
  • An image of a 52 Gallon Marine Fresh Water Tank | BOAT48W

    60 Gallon Marine Fresh Water Tank | BOAT59W

    This 60-gallon Ronco marine fresh water tank (BOAT59W) is built for onboard potable water storage on boats and watercraft. Measuring 40" x 25" x 15 1/2", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended trips...

    $480.02
    Add to Cart
  • An image of a 45 Gallon RV Fresh Water Tank | BOAT47W

    60 Gallon Marine Holding Tank | BOAT59W

    This 60-gallon Ronco marine holding tank (BOAT59W) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 40" x 25" x 15 1/2", it is designed to fit common marine compartment layouts while providing dependable...

    $480.02
    Add to Cart
  • An image of a 20 Gallon RV Fresh Water Tank | RV72W

    60 Gallon Marine Fresh Water Tank | BOAT54W

    This 60-gallon Ronco marine fresh water tank (BOAT54W) is built for onboard potable water storage on boats and watercraft. Measuring 36 1/4" x 30 1/4" x 14 1/2", it fits a wide range of vessel layouts and provides reliable fresh water capacity for...

    $480.02
    Add to Cart