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

  • An image of a 28 Gallon Marine Fresh Water Tank | B273

    12 Gallon Marine Fresh Water Tank | B255

    This 12-gallon Ronco marine fresh water tank (B255) is built for onboard potable water storage on boats and watercraft. Measuring 17" x 17" x 11", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended trips on the...

    $232.98
    Add to Cart
  • An image of a 28 Gallon Marine Holding Tank | B273

    12 Gallon Marine Holding Tank | B255

    This 12-gallon Ronco marine holding tank (B255) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 17" x 17" x 11", it is designed to fit common marine compartment layouts while providing dependable waste...

    $232.98
    Add to Cart
  • An image of a 70 Gallon Marine Fresh Water Tank | B296

    12 Gallon Marine Fresh Water Tank | B199

    This 12-gallon Ronco marine fresh water tank (B199) is built for onboard potable water storage on boats and watercraft. Measuring 23 1/2" x 17 5/8" x 9 7/8", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended...

    $281.18
    Add to Cart
  • An image of a 70 Gallon Marine Holding Tank | B296

    12 Gallon Marine Holding Tank | B199

    This 12-gallon Ronco marine holding tank (B199) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 23 1/2" x 17 5/8" x 9 7/8", it is designed to fit common marine compartment layouts while providing dependable...

    $281.18
    Add to Cart
  • An image of a 103 Gallon PP Ronco White Rectangular Open Top Tank | 36X24X30PP

    12 Gallon Marine Fresh Water Tank | B124

    This 12-gallon Ronco marine fresh water tank (B124) is built for onboard potable water storage on boats and watercraft. Measuring 20" x 12" x 12", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended trips on the...

    $232.98
    Add to Cart
  • An image of a 103 Gallon PE Ronco White Rectangular Open Top Tank | 36X24X30PE

    12 Gallon Marine Holding Tank | B124

    This 12-gallon Ronco marine holding tank (B124) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 20" x 12" x 12", it is designed to fit common marine compartment layouts while providing dependable waste...

    $232.98
    Add to Cart
  • An image of a 14 Gallon Marine Holding Tank | B160

    12 Gallon Marine Fresh Water Tank | B105

    This 12-gallon Ronco marine fresh water tank (B105) is built for onboard potable water storage on boats and watercraft. Measuring 17 1/2" x 14" x 12", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended trips on...

    $232.98
    Add to Cart
  • An image of a 18 Gallon Marine Fresh Water Tank | B159

    12 Gallon Marine Holding Tank | B105

    This 12-gallon Ronco marine holding tank (B105) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 17 1/2" x 14" x 12", it is designed to fit common marine compartment layouts while providing dependable waste...

    $232.98
    Add to Cart
  • 12 Gallon RV Water Tank L-2. Technical drawing of a polyethylene water tank designed for your rv.

    12 Gallon RV Water Tank L-2

    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 12 Gallon RV Water Tank, Part# L-2, is engineered to meet the requirements of mobile water...

    MSRP: $103.68
    $98.58
    Add to Cart
  • 12 Gallon Marine Water Tank ML-2. Technical drawing of a polyethylene water tank designed for marine vessels.

    12 Gallon Marine Water Tank ML-2

    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 12 Gallon Marine Water Tank, Part# ML-2, is engineered to meet the requirements of mobile...

    MSRP: $195.03
    $185.43
    Add to Cart
  • 12 Gallon RV Holding Tank H-667. Technical drawing of a polyethylene holding tank designed for your rv and camper.

    12 Gallon RV Holding Tank H-667

    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 12 Gallon RV Holding Tank, Part# H-667, is engineered to meet the requirements of mobile...

    MSRP: $142.56
    $135.54
    Add to Cart
  • 12 Gallon RV Holding Tank H-575 . Technical drawing of a polyethylene holding tank designed for your rv and camper.

    12 Gallon RV Holding Tank H-575

    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 12 Gallon RV Holding Tank, Part# H-575, is engineered to meet the requirements of mobile...

    MSRP: $90.72
    $86.25
    Add to Cart
  • 12 Gallon RV Holding Tank H-322 . Technical drawing of a polyethylene holding tank designed for your rv and camper.

    12 Gallon RV Holding Tank H-322

    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 12 Gallon RV Holding Tank, Part# H-322, is engineered to meet the requirements of mobile...

    MSRP: $142.56
    $135.54
    Add to Cart
  • 12 Gallon RV Holding Tank H-292 . Technical drawing of a polyethylene holding tank designed for your rv and camper.

    12 Gallon RV Holding Tank H-292

    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 12 Gallon RV Holding Tank, Part# H-292, is engineered to meet the requirements of mobile...

    MSRP: $116.64
    $110.90
    Add to Cart
  • 12 Gallon RV Holding Tank H-291 . Technical drawing of a polyethylene holding tank designed for your rv and camper.

    12 Gallon RV Holding Tank H-291

    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 12 Gallon RV Holding Tank, Part# H-291, is engineered to meet the requirements of mobile...

    MSRP: $110.16
    $104.74
    Add to Cart
  • 12 Gallon RV Holding Tank H-219L. Technical drawing of a polyethylene holding tank designed for your rv and camper.

    12 Gallon RV Holding Tank H-219L

    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 12 Gallon RV Holding Tank, Part# H-219L, is engineered to meet the requirements of mobile...

    MSRP: $170.95
    $162.53
    Add to Cart
  • An image of a 30 Gallon Marine Fresh Water Tank | B179

    13 Gallon RV Fresh Water Tank | RVB266

    This 13-gallon Ronco RV fresh water tank (RVB266) provides reliable potable water storage for recreational vehicles. Measuring 18 1/4" x 14 3/8" x 13 1/8", it is sized to fit a range of RV builds and offers dependable water capacity for trips of all...

    $250.05
    Add to Cart
  • An image of a 16 Gallon Marine Fresh Water Tank | B215

    13 Gallon RV Fresh Water Tank | RVB262

    This 13-gallon Ronco RV fresh water tank (RVB262) provides reliable potable water storage for recreational vehicles. Measuring 15 7/8" x 15 1/8" x 14 1/2", it is sized to fit a range of RV builds and offers dependable water capacity for trips of all...

    $181.76
    Add to Cart
  • An image of a 18 Gallon RV Fresh Water Tank | RVB369

    13 Gallon RV Holding Tank | RV46H

    This 13-gallon Ronco RV holding tank (RV46H) is designed for blackwater and greywater waste storage in recreational vehicles. Measuring 30" x 52" x 5", it fits common RV underbelly and compartment configurations while providing reliable waste containment...

    $386.63
    Add to Cart
  • An image of a 4 Gallon Marine Holding Tank | B269

    13 Gallon RV Holding Tank | RV26H

    This 13-gallon Ronco RV holding tank (RV26H) is designed for blackwater and greywater waste storage in recreational vehicles. Measuring 29" x 17" x 11", it fits common RV underbelly and compartment configurations while providing reliable waste...

    $210.88
    Add to Cart
  • An image of a 20 Gallon Marine Fresh Water Tank | B236

    13 Gallon Marine Fresh Water Tank | BOAT37W

    This 13-gallon Ronco marine fresh water tank (BOAT37W) is built for onboard potable water storage on boats and watercraft. Measuring 29 3/4" x 16" x 7 1/2", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended...

    $233.99
    Add to Cart
  • An image of a 20 Gallon Marine Holding Tank | B236

    13 Gallon Marine Holding Tank | BOAT37W

    This 13-gallon Ronco marine holding tank (BOAT37W) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 29 3/4" x 16" x 7 1/2", it is designed to fit common marine compartment layouts while providing dependable...

    $233.99
    Add to Cart
  • An image of a 210 Gallon RV Fresh Water Tank | B302

    13 Gallon Marine Fresh Water Tank | B476

    This 13-gallon Ronco marine fresh water tank (B476) is built for onboard potable water storage on boats and watercraft. Measuring 23" x 18" x 15 1/4", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended trips on...

    $269.13
    Add to Cart
  • An image of a 210 Gallon Marine Fresh Water Tank | B302

    13 Gallon Marine Holding Tank | B476

    This 13-gallon Ronco marine holding tank (B476) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 23" x 18" x 15 1/4", it is designed to fit common marine compartment layouts while providing dependable waste...

    $269.13
    Add to Cart
  • An image of a 11 Gallon PP Ronco White Rectangular Open Top Tank | 24X4X30PP

    13 Gallon Marine Fresh Water Tank | B436

    This 13-gallon Ronco marine fresh water tank (B436) is built for onboard potable water storage on boats and watercraft. Measuring 36 1/2" x 11" x 10", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended trips on...

    $304.28
    Add to Cart
  • An image of a 11 Gallon PE Ronco White Rectangular Open Top Tank | 24X4X30PE

    13 Gallon Marine Holding Tank | B436

    This 13-gallon Ronco marine holding tank (B436) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 36 1/2" x 11" x 10", it is designed to fit common marine compartment layouts while providing dependable waste...

    $304.28
    Add to Cart
  • An image of a 7 Gallon Marine Holding Tank | B275

    13 Gallon Marine Fresh Water Tank | B419

    This 13-gallon Ronco marine fresh water tank (B419) is built for onboard potable water storage on boats and watercraft. Measuring 36 1/2" x 17" x 10", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended trips on...

    $362.53
    Add to Cart
  • An image of a 14 Gallon Marine Fresh Water Tank | B274

    13 Gallon Marine Holding Tank | B419

    This 13-gallon Ronco marine holding tank (B419) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 36 1/2" x 17" x 10", it is designed to fit common marine compartment layouts while providing dependable waste...

    $362.53
    Add to Cart
  • An image of a 30 Gallon Marine Holding Tank | B179

    13 Gallon Marine Fresh Water Tank | B266

    This 13-gallon Ronco marine fresh water tank (B266) is built for onboard potable water storage on boats and watercraft. Measuring 18 1/4" x 14 3/8" x 13 1/8", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended...

    $232.98
    Add to Cart
  • An image of a 50 Gallon Marine Fresh Water Tank | B178

    13 Gallon Marine Holding Tank | B266

    This 13-gallon Ronco marine holding tank (B266) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 18 1/4" x 14 3/8" x 13 1/8", it is designed to fit common marine compartment layouts while providing dependable...

    $232.98
    Add to Cart
  • An image of a 16 Gallon Marine Holding Tank | B215

    13 Gallon Marine Fresh Water Tank | B262

    This 13-gallon Ronco marine fresh water tank (B262) is built for onboard potable water storage on boats and watercraft. Measuring 15 7/8" x 15 1/8" x 14 1/2", it fits a wide range of vessel layouts and provides reliable fresh water capacity for extended...

    $232.98
    Add to Cart
  • An image of a 18 Gallon Marine Fresh Water Tank | B214

    13 Gallon Marine Holding Tank | B262

    This 13-gallon Ronco marine holding tank (B262) is purpose-built for blackwater and greywater waste storage on boats and watercraft. Measuring 15 7/8" x 15 1/8" x 14 1/2", it is designed to fit common marine compartment layouts while providing dependable...

    $232.98
    Add to Cart