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

RV & Marine Tanks

  • Image of a 15 Gallon Trionic Marine Fresh Water Tank

    15 Gallon Trionic Marine Fresh Water Tank | WH-2015

    The 15 Gallon Trionic Marine Fresh Water Tank offered by One Clarion is a versatile and portable solution for your marine water storage needs. With its rectangular shape and above ground usability, this tank is designed to fit seamlessly into your boat...

    $301.26
    Add to Cart
  • Image of a 15 Gallon Trionic Marine Holding Tank

    15 Gallon Trionic Marine Holding Tank | WH-2015

    The 15 Gallon Trionic Marine Holding Tank is a versatile and portable solution for your marine waste management needs. With its rectangular shape and above ground usability, this tank is designed to fit seamlessly into your boat or marine vessel. Made...

    $301.26
    Add to Cart
  • 15 Gallon RV Water Tank W-543. Technical drawing of a polyethylene water tank designed for your rv.

    15 Gallon RV Water Tank W-543

    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 15 Gallon RV Water Tank, Part# W-543, is engineered to meet the requirements of mobile water...

    MSRP: $142.56
    $135.54
    Add to Cart
  • 15 Gallon RV Water Tank W-489. Technical drawing of a polyethylene water tank designed for your rv.

    15 Gallon RV Water Tank W-489

    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 15 Gallon RV Water Tank, Part# W-489, is engineered to meet the requirements of mobile water...

    MSRP: $90.72
    $86.25
    Add to Cart
  • 15 Gallon RV Water Tank W-366. Technical drawing of a polyethylene water tank designed for your rv.

    15 Gallon RV Water Tank W-366

    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 15 Gallon RV Water Tank, Part# W-366, is engineered to meet the requirements of mobile water...

    MSRP: $116.64
    $110.90
    Add to Cart
  • 15 Gallon RV Water Tank W-355. Technical drawing of a polyethylene water tank designed for your rv.

    15 Gallon RV Water Tank W-355

    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 15 Gallon RV Water Tank, Part# W-355, is engineered to meet the requirements of mobile water...

    MSRP: $103.68
    $98.58
    Add to Cart
  • 15 Gallon RV Water Tank W-327. Technical drawing of a polyethylene water tank designed for your rv.

    15 Gallon RV Water Tank W-327

    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 15 Gallon RV Water Tank, Part# W-327, is engineered to meet the requirements of mobile water...

    MSRP: $116.64
    $110.90
    Add to Cart
  • 15 Gallon RV Water Tank L-3. Technical drawing of a polyethylene water tank designed for your rv.

    15 Gallon RV Water Tank L-3

    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 15 Gallon RV Water Tank, Part# L-3, is engineered to meet the requirements of mobile water...

    MSRP: $116.64
    $110.90
    Add to Cart
  • 15 Gallon Marine Water Tank MW-543. Technical drawing of a polyethylene water tank designed for marine vessels.

    15 Gallon Marine Water Tank MW-543

    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 15 Gallon Marine Water Tank, Part# MW-543, is engineered to meet the requirements of mobile...

    MSRP: $346.52
    $329.47
    Add to Cart
  • 15 Gallon Marine Water Tank MW-489. Technical drawing of a polyethylene water tank designed for marine vessels.

    15 Gallon Marine Water Tank MW-489

    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 15 Gallon Marine Water Tank, Part# MW-489, is engineered to meet the requirements of mobile...

    MSRP: $185.41
    $176.28
    Add to Cart
  • 15 Gallon Marine Water Tank MW-366. Technical drawing of a polyethylene water tank designed for marine vessels.

    15 Gallon Marine Water Tank MW-366

    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 15 Gallon Marine Water Tank, Part# MW-366, is engineered to meet the requirements of mobile...

    MSRP: $246.93
    $234.77
    Add to Cart
  • 15 Gallon Marine Water Tank MW-355. Technical drawing of a polyethylene water tank designed for marine vessels.

    15 Gallon Marine Water Tank MW-355

    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 15 Gallon Marine Water Tank, Part# MW-355, is engineered to meet the requirements of mobile...

    MSRP: $182.38
    $173.40
    Add to Cart