Marine Water Tanks

These NSF and FDA compliant marine water storage tanks are made to be incredibly strong, nearly unbreakable, and are very affordable. Plastic marine water tanks (poly) are available in nearly every size and shape. Made from one piece of thick poly, there are no seams so less opportunity for leaking, and made with a rotomold process for superior strength. You won’t find better-made marine fresh water 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. These custom fitted marine water tanks are built to go the distance.   

*Note: 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 marine water tanks, marine fresh water tanks, plastic marine water tanks, poly marine water tanks, custom marine water tanks, and more!

We have 100’s of sizes ranging from 2 gallons, 40 gallons, 50 gallons, 100 gallon marine water tanks.  They range in size up to 250 gallons for these poly marine fresh water tanks.

Looking for something else? Chances are, we have it, and at affordable prices too!  Just call us and ask!

Pick the size and shape you need from the list. Mark up the drawing with your fittings placement. Call us with any questions!

Marine Water Tanks

  • 90 Gallon Marine Water Tank MW-552. Technical drawing of a polyethylene water tank designed for marine vessels.

    90 Gallon Marine Water Tank MW-552

    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 90 Gallon Marine Water Tank, Part# MW-552, is engineered to meet the requirements of mobile...

    MSRP: $953.61
    $906.66
    Add to Cart
  • 90 Gallon Marine Water Tank MW-539. Technical drawing of a polyethylene water tank designed for marine vessels.

    90 Gallon Marine Water Tank MW-539

    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 90 Gallon Marine Water Tank, Part# MW-539, is engineered to meet the requirements of mobile...

    MSRP: $734.76
    $698.59
    Add to Cart
  • An image of a 40 Gallon RV Holding Tank | RV84H

    92 Gallon Marine Fresh Water Tank | B483

    Introducing the 92 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is specifically designed for marine use, making it perfect for boating and other water activities. With its rectangular shape, it offers a space-efficient solution for...

    $666.81
    Add to Cart
  • An image of a 50 Gallon RV Fresh Water Tank | RVB210

    92 Gallon Marine Fresh Water Tank | B387

    Introducing the 92 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is specifically designed for marine use, making it perfect for boats and other water vessels. With its rectangular shape, it offers a space-efficient solution for...

    $666.81
    Add to Cart
  • An image of a 80 Gallon Marine Holding Tank | B458

    93 Gallon Marine Fresh Water Tank | BOAT66W

    Introducing the 93 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is specifically designed for marine use, making it perfect for boating and other water activities. With its rectangular shape, it offers a spacious capacity of 93...

    $632.67
    Add to Cart
  • 93 Gallon Marine Water Tank MW-353. Technical drawing of a polyethylene water tank designed for marine vessels.

    93 Gallon Marine Water Tank MW-353

    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 93 Gallon Marine Water Tank, Part# MW-353, is engineered to meet the requirements of mobile...

    MSRP: $669.91
    $636.93
    Add to Cart
  • An image of a 130 Gallon Marine Fresh Water Tank | B356

    95 Gallon Marine Fresh Water Tank | B448

    Introducing the 95 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is specifically designed for marine use, making it perfect for boats and other water vessels. With its rectangular shape, it offers a space-efficient solution for...

    $819.46
    Add to Cart
  • An image of a 43 Gallon RV Fresh Water Tank | RVB220

    95 Gallon Marine Fresh Water Tank | B354

    Introducing the 95 Gallon Marine Fresh Water Tank by One Clarion. This marine water tank is designed with a rectangular shape, making it easy to fit in various spaces. Its portable nature allows for convenient transportation, while its above ground...

    $689.91
    Add to Cart
  • An image of a 50 Gallon Ronco White Vertical Storage Tank | RPV50

    95 Gallon Marine Fresh Water Tank | B259

    Introducing the 95 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is specifically designed for marine use, making it perfect for boats and other watercraft. With its rectangular shape, it is easy to fit into tight spaces and maximize...

    $689.91
    Add to Cart
  • 95 Gallon Marine Water Tank MW-544. Technical drawing of a polyethylene water tank designed for marine vessels.

    95 Gallon Marine Water Tank MW-544

    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 95 Gallon Marine Water Tank, Part# MW-544, is engineered to meet the requirements of mobile...

    MSRP: $766.03
    $728.31
    Add to Cart
  • 95 Gallon Marine Water Tank MW-326. Technical drawing of a polyethylene water tank designed for marine vessels.

    95 Gallon Marine Water Tank MW-326

    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 95 Gallon Marine Water Tank, Part# MW-326, is engineered to meet the requirements of mobile...

    MSRP: $719.87
    $684.42
    Add to Cart
  • 95 Gallon Marine Water Tank MW-246. Technical drawing of a polyethylene water tank designed for marine vessels.

    95 Gallon Marine Water Tank MW-246

    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 95 Gallon Marine Water Tank, Part# MW-246, is engineered to meet the requirements of mobile...

    MSRP: $722.15
    $686.60
    Add to Cart