Marine Water Tanks
Boat Water Tank
Our high-quality marine water tanks are crafted from FDA-approved virgin polyethylene plastic resins, making them ideal for marine boat tanks, graywater tanks, RV tanks, ballast tanks, and more. These boat water tanks are seamless, one-piece tanks that keep your water safe from contamination and leakage. We customize our strong and durable tanks to your dimensions for a perfect fit, and can spin-weld fittings to make sure your marine holding tank connects perfectly.
Our marine fresh water tanks comply with FDA regulation CFR 177.1520 and Coast Guard Standards making them suitable for potable water storage. Completely enclosed, our plastic marine tanks have 3/8" thick walls, giving your tank sturdiness for a long service life. Let us help you with projects requiring a unique size or shape to make sure you have the right tank fit. Call to talk with one of our team members today!
See our Marine Water Tanks (pdf) for more details.Questions about our marine water tanks? We can help! Call our team at 1-863-270-8118 or fill out our quote request form to discuss your requirements.
Custom Marine Water Tanks
Made with FDA-approved, virgin polyethylene plastic resin, our marine water tanks are perfect for storing potable water in boats and marine vessels such as sailboats, yachts, or deep sea fishing boats. Designed with a one-piece marine tank, your water-holding tank is both durable and practical. Because our plastic marine tanks are seamless, they don’t crack or weaken over time. Tanks have female NPT openings in the same position on one end, making them ideal for any marine plumbing. Cost effective and eco-friendly, boat water tanks come with spin weld fittings to make sure your tank has the perfect fit. One Clarion is committed providing you with the highest quality marine tanks on the market!
Bow Shaped Water Tanks

Part No. | Capacity | Length | Width | Depth |
---|---|---|---|---|
W-359 | 56 gallons | 90 | 17.5 | 12 |
W-360 | 56 gallons | 90 | 17.5 | 12 |
W-361 | 16 gallons | 15 | 25.25 | 13 |
W-363 | 35 gallons | 66 | 15.5 | 9.81 |
W-365 | 25 gallons | 59 | 13.5 | 7.5 |
W-366 | 15 gallons | 36 | 13.5 | 7.5 |
W-366 | 8 gallons | 19.5 | 13.5 | 7.5 |
W-366 | 12 gallons | 24 | 15 | 12 |
See Full Listing of Marine Water Tank Sizes
Rectangle Shaped Water Tanks

Part No. | Capacity | Length | Width | Depth |
---|---|---|---|---|
L-1 | 10 gallons | 18 | 16 | 8 |
L-2 | 12 gallons | 24 | 16 | 8 |
L-3 | 15 gallons | 30 | 16 | 8 |
L-4 | 20 gallons | 36 | 16 | 8 |
L-5 | 25 gallons | 48 | 16 | 8 |
W-1 | 40 gallons | 58 | 14 | 12 |
W-101 | 100 gallons | 50 | 40 | 12 |
W-108 | 145 gallons | 50 | 31.25 | 22 |
W-12 | 53 gallons | 30.25 | 24.5 | 17.25 |
W-17 | 40 gallons | 41 | 15.25 | 15.5 |
W-2 | 27 gallons | 35 | 15 | 13 |
W-20 | 25 gallons | 42 | 16 | 10 |
See Full Listing of Marine Water Tank Sizes
Wedge Shaped Water Tanks

Part No. | Capacity | Length | Width | Depth |
---|---|---|---|---|
W-211 | 72 gallons | 61.75 | 24 | 13 |
W-215 | 100 gallons | 78 | 26 | 14 |
W-224 | 88 gallons | 73.75 | 24.25 | 12.75 |
W-273 | 70 gallons | 73.75 | 24.25 | 10.75 |
W-274 | 65 gallons | 69 | 24.25 | 10.75 |
W-281 | 81 gallons | 70 | 26.75 | 11.75 |
W-303 | 97 gallons | 73 | 24.75 | 14 |
W-349 | 82 gallons | 48 | 40.5 | 11 |
W-350 | 108 gallons | 76 | 40 | 10 |
W-353 | 93 gallons | 59 | 36.5 | 11.375 |
W-358 | 8 gallons | 19.75 | 17.75 | 8 |
W-374 | 107 gallons | 76 | 38.5 | 10.125 |
W-375 | 17 gallons | 24.5 | 22 | 9 |
W-93 | 150 gallons | 67.5 | 40.5 | 14.25 |
See Full Listing of Marine Water Tank Sizes
Give us a call at 1-863-270-8118 or fill out our quote request form to discuss your roto mold project requirements.
Our Marine Water Tank Process
We are dedicated to providing a collaborative and efficient process for your custom marine water tank project. Our tanks don’t come with pre-drilled holes, so we have a blank canvas to place holes and fittings exactly where you need them. Your custom boat water tank can pivot to fit your available space.
- Start by simply filling in a tank drawing with your tank dimensions and specifications. Show on your drawing where you need the ports on your tank. Be as precise as you can with measurements showing location.
- Once our team reviews your drawing, they will contact you with feedback and suggestions.
- Our team works with you until you're satisfied with the design, and then processes your order.
- We encourage you to provide the most specific information available to fit sizes and locations for your tank. If you're not sure about all the details, our team is ready to guide you through the process, making any changes you need.

*Mounting straps are not included with this tank, and it is not for use with gasoline fuel storage. If you need a different type of tank, our team can help you find the right custom tank to fit your specific needs.
Need pricing for marine water tanks? Give our sales team a call at 1-863-270-8118 or fill out our quote request form to discuss your boat tank project requirements.
Roto Molding for Marine Water Tanks
Your marine water tank starts with the process of roto molding, where heated virgin polyethylene resin is melted inside a hollow, closed mold. The mold, placed in the cast, is heated to 260°C – 370°C. As the mold rotates, it is evenly coated with the polyethylene resin, resulting in smooth walls with consistent thickness. This durable marine water tank makes a strong, seamless, longer-lasting water tank.
Marine Water Tank Accessories
One Clarion is proud to be an industry leader by making sure we meet your needs. We offer customizable tank dimensions to fit your specifications, and install spin weld fittings upon request. If your project requires a unique size or shape, we can even create a custom tool to accommodate your needs.
Our polyethylene fittings for our holding tanks and fresh water tanks are made through spin welding. This simple process produces a strong, durable permanent joint link and a great finish. We can make fittings for your tanks, ensuring a correct fit and are watertight. | ![]() |
We also offer a variety of compartments, including rounded corner open ended, square corner open ended, and square corner top and end compartments in a variety of sizes. See: List of Boat Storage Containers |
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We have several battery boxes available to keep your marine battery from tipping or accidentally shorting out, as well as protecting it from corroding. See: Battery boxes sizes |
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Sustainable Custom Plastic Storage
Our custom plastic marine tank gives a sustainable solution for environmental friendly water storage. Manufactured with non-toxic material, tanks have a low carbon emission during their life cycle. Our tanks can withstand corrosion, are leak proof, resist UV damage, and last longer than other tanks. Reduce your carbon footprint with our flexible, cost-effective plastic marine tanks.
Questions? We can help! Call us at 1-863-270-8118 or request a price quote.
Our Marine Water Tank provides a wide range of customization for your tank size, shape and fit. We create the perfect fresh water tank for your boat. Talk with one of our team members to find out more about our custom boat water tanks and other marine tanks to fit your project needs.