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

  • An image of a 30 Gallon Marine Fresh Water Tank | B112

    16 Gallon Marine Fresh Water Tank | B500

    Upgrade your marine vessel with the 16 Gallon Marine Fresh Water Tank from One Clarion. This rectangular tank is designed for portable use and is suitable for above ground environments. Made from polyethylene in a natural white color, this tank is 37...

    $246.04
    Add to Cart
  • An image of a 30 Gallon Marine Holding Tank | B112

    16 Gallon Marine Fresh Water Tank | B399

    The 16 Gallon Marine Fresh Water Tank by One Clarion is the perfect solution for your portable marine water needs. This rectangular tank is designed for above ground use and is made from high-quality polyethylene material in a natural white color. The...

    $326.38
    Add to Cart
  • An image of a 40 Gallon Marine Holding Tank | B221

    16 Gallon Marine Fresh Water Tank | B398

    Introducing the 16 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is designed specifically for marine use, making it the perfect solution for storing and transporting fresh water on your boat or yacht. With a rectangular shape and a...

    $327.38
    Add to Cart
  • An image of a 58 Gallon RV Fresh Water Tank | RV60W

    16 Gallon Marine Fresh Water Tank | B373

    Upgrade your marine vessel with the 16 Gallon Marine Fresh Water Tank from One Clarion. This rectangular tank is designed for portable use and is suitable for above ground environments. Made from polyethylene in a natural white color, this tank measures...

    $281.18
    Add to Cart
  • An image of a 80 Gallon RV Fresh Water Tank | B230

    16 Gallon Marine Fresh Water Tank | B364

    Introducing the 16 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is designed specifically for marine use, making it the perfect solution for storing and transporting fresh water on your boat or yacht. With a rectangular shape and a...

    $304.28
    Add to Cart
  • An image of a 30 Gallon Marine Fresh Water Tank | B191

    16 Gallon Marine Fresh Water Tank | B215

    The 16 Gallon Marine Fresh Water Tank offered by One Clarion is a versatile and portable solution for your marine water storage needs. With a rectangular tank shape, this tank is designed to be easily transported and used above ground. The tank is made...

    $281.18
    Add to Cart
  • An image of a 5 Gallon Marine Fresh Water Tank | B303

    16 Gallon Marine Fresh Water Tank | B125

    The 16 Gallon 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 or marine...

    $269.13
    Add to Cart
  • An image of a 6 Gallon Marine Fresh Water Tank | B277

    16 Gallon Marine Fresh Water Tank | B122

    Introducing the 16 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is designed specifically for marine use, making it the perfect solution for storing and transporting fresh water on your boat or yacht. With a rectangular shape and a...

    $246.04
    Add to Cart
  • An image of a 25 Gallon Marine Holding Tank | B163

    16 Gallon Marine Fresh Water Tank | B111

    Introducing the 16 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is designed specifically for marine use, making it the perfect solution for your fresh water needs while out on the water. With a rectangular shape and a capacity of 16...

    $281.18
    Add to Cart
  • An image of a 30 Gallon Marine Holding Tank | B350

    16 Gallon Marine Fresh Water Tank | B109

    Introducing the 16 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is designed specifically for marine use, making it the perfect solution for boating and other water activities. With a rectangular shape and a capacity of 16 gallons,...

    $246.04
    Add to Cart
  • An image of a 115 Gallon RV Fresh Water Tank | B466

    16 Gallon Marine Fresh Water Tank | B107

    The 16 Gallon 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 or marine...

    $246.04
    Add to Cart
  • An image of a 14 Gallon Marine Holding Tank | B238

    16 Gallon Marine Fresh Water Tank | B106

    The 16 Gallon 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 compact dimensions of 16" Length x 16" Width x 16" Height, this tank is designed to fit...

    $232.98
    Add to Cart