Custom Plastic Marine Water Tanks and Marine Waste Holding Tanks (Freshwater, Grey Water & Wastewater)
At Miller Plastic Products, we manufacture custom marine water tanks to suit a variety of needs and applications. Many larger boats have a clean water system and a wastewater system. Clean water is also known as potable or fresh water; Wastewater is known as black water or gray water.
If there’s an RV or marine water tank available in stainless steel, or aluminum, we can fabricate the same shape and size container out of lighter-weight plastic materials, including:
Request a quote for a custom marine holding tank from Miller Plastic Products below. These custom fabricated tanks start at $1,491.
The kinds of plastic tanks we can fabricate to your exact specifications include:
Fresh Water Tanks
Wastewater Tanks
Grey Water Tanks

We offer a wide selection of custom plastic marine water tanks, marine waste holding tanks, and RV tanks in any size or shape to fit your need. Our tanks can also be heated for use in freezing weather. The kinds of marine tanks we can fabricate to your exact specifications include:
Bottom Dump Waste Water Tanks
Recessed End Dump Holding Tanks
End Dump Holding Tanks
Bow Shaped Water Tanks
L-Shaped Holding and Water Tanks
Side Dump Holding Tanks
Wastewater Tanks
Fresh Water Tanks
Grey Water & Black Water Tanks
Holding Tanks
Port and Starboard Tanks
Bow and Stern
Get A Custom Plastic Tank Quote
Our experience can help you choose the right material for your particular custom plastic marine water tank, RV tank, or marine waste holding tank. We’re just a phone call or click away.
We offer free design assistance and can provide 2D or 3D drawings using AutoCAD and SOLIDWORKS
Build A TankWe offer free design assistance and can provide 2D or 3D drawings using AutoCAD and SOLIDWORKS
Our tanks are engineered using FEA (Finite Element Analysis) to maximize performance and allow for minimal bowing of the fabrication.


Materials