45 Litre Universal Underfloor Waste Water Tank Kit

This 45-litre universal underfloor waste water tank is ideal for campervan and motorhome conversions of all layouts. Designed for flexible installation across a wide range of vehicles, it offers a discreet, durable solution for managing grey water safely beneath the van.

Manufactured from high-quality, corrosion-resistant polyethylene, the tank features a matt black finish for a low-visibility, long-lasting underfloor installation. Its hygienic, algae-resistant construction ensures dependable performance for long-term builds.

A large threaded top access hatch allows the installation of internal accessories, pumps or sensors, and also provides access for periodic cleaning.

What’s Included

1 × 45L Water Tank
(Approx. dimensions: 500mm (L) × 400mm (W) × 255mm (H))

1 × 1/2" Elbow for connecting the breather

1 × 3/4" Elbow for connecting the waste outlet pipe

1 × 1m long 1/2" Breather Pipe

1 × 2m long 3/4" Convoluted Black Waste Hose

1 × 3/4" Drain Tap (fits directly into the tank)

1 × Universal Tank/Strap Fitting Kit with fixings

Locating & Installation Guide

This universal tank can be installed widthways or lengthways, depending on your vehicle’s chassis layout and available space. Ideal mounting locations include:

between chassis rails

beside the fuel tank

ahead of the rear axle

in any underfloor cavity with sufficient depth and clearance

For correct installation:

Mount the tank with the service hatch facing upward.

Ensure all hoses have natural fall for drainage.

Position the breather line as high as possible to prevent siphoning.

Avoid mounting near exhaust heat sources unless shielded.

Important Information

Water level senders are available separately, including models compatible with Victron Energy and SRNE systems. (Here)

Tanks may contain traces of water on arrival due to leak testing—this is normal.

Clean the tank thoroughly before first use.

Specifications

Capacity: 45 litres

Dimensions: 500mm (L) × 400mm (W) × 255mm (H)

Dry Weight: approx. 4kg