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

  • 2 Gallon Marine Water Tank MW-364

    2 Gallon Marine Water Tank MW-364

    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 2 Gallon Marine Water Tank, Part# MW-364, is engineered to meet the requirements of mobile...

    MSRP: $81.40
    $77.39
    Add to Cart
  • An image of a 14 Gallon PE Ronco White Rectangular Open Top Tank | 12X12X24PE

    3 Gallon Marine Fresh Water Tank | BOAT13W

    Introducing the 3 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 is easy to fit into tight spaces on your...

    $128.53
    Add to Cart
  • An image of a 16 Gallon PE Ronco White Rectangular Open Top Tank | 18X12X18PE

    3 Gallon Marine Fresh Water Tank | B267

    Introducing the 3 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 is easy to fit into tight spaces on your...

    $139.59
    Add to Cart
  • An image of a 54 Gallon PP Ronco White Rectangular Open Top Tank | 24X24X24PP

    4 Gallon Marine Fresh Water Tank | B525

    The 4 Gallon Marine Fresh Water Tank from One Clarion is a portable and above ground tank designed specifically for marine use. Its rectangular shape and compact size make it easy to transport and install on boats or other marine vessels. Made from...

    $151.64
    Add to Cart
  • An image of a 150 Gallon PP Ronco White Cylindrical Open Top Tank | 150PP

    4 Gallon Marine Fresh Water Tank | B269

    The 4 Gallon Marine Fresh Water Tank by One Clarion is a rectangular-shaped portable tank designed for above ground use. This tank is not pressurized, making it easy to handle and transport. The tank is made of polyethylene and comes in a natural white...

    $139.59
    Add to Cart
  • Image of a 4 Gallon Trionic Marine Fresh Water Tank

    4 Gallon Trionic Marine Fresh Water Tank | WH-2004

    Introducing the 4 Gallon Trionic Marine Fresh Water Tank by One Clarion. This portable marine water tank is designed with a rectangular shape, making it easy to fit in tight spaces on your boat or yacht. With its above ground usability, you can...

    $210.88
    Add to Cart
  • An image of a 23 Gallon Marine Holding Tank | B142

    5 Gallon Marine Fresh Water Tank | B410

    Introducing the 5 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 is easy to fit into tight spaces on your...

    $151.64
    Add to Cart
  • An image of a 86 Gallon PE Ronco White Rectangular Open Top Tank | 30X24X30PE

    5 Gallon Marine Fresh Water Tank | B390

    Introducing the 5 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 is easy to fit into tight spaces on your...

    $151.64
    Add to Cart
  • An image of a 12 Gallon PP Ronco White Rectangular Open Top Tank | 18X14X12PP

    5 Gallon Marine Fresh Water Tank | B377

    Introducing the 5 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 is easy to store and transport. The tank...

    $151.64
    Add to Cart
  • An image of a 17 Gallon PE Ronco White Cylindrical Open Top Tank | 17LDPE

    5 Gallon Marine Fresh Water Tank | B322

    Introducing the 5 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is specifically designed for marine use, making it the perfect solution for storing and transporting fresh water on your boat or yacht. With its rectangular shape, it...

    $151.64
    Add to Cart
  • An image of a 86 Gallon PP Ronco White Rectangular Open Top Tank | 30X24X28PP

    5 Gallon Marine Fresh Water Tank | B303

    Introducing the 5 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 is easy to store and transport. The tank...

    $152.64
    Add to Cart
  • An image of a 65 Gallon PE Ronco White Cylindrical Open Top Tank | 65LDPE

    5 Gallon Marine Fresh Water Tank | B268

    Introducing the 5 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 is easy to store and transport. The tank...

    $139.59
    Add to Cart