The 18 foot unit comes with three tanks: a fresh water, grey water and a black water tank. The fresh water tank is located in the front of the unit. Both the grey and black water tank are located at the back. This positioning is part of the total design strategy that results in an optimal weight balance.

All tanks are made of HDPE (High-density polyethylene). HDPE is known for its large strength-to-density ratio and is corrosion free. It is also very hard, opaque and can withstand higher temperatures (120 °C/ 248 °F for short periods, 110 °C /230 °F continuously).

The tank walls have a thickness of 10 mm and are welded on both sides. All tanks are fitted with panels inside to give the tank extra strength and to prevent sudden movement of the water. This is important to prevent big weight shifts while driving.

To ensure access to the clean water supply, the 18 foot comes with a high quality super silent pressure pump. For inspection, each tank is fitted with a removable watertight and pressure resistant cover. This enables easy cleaning and gives you direct access to your drinking water in the unlikely event of pump/power failure.

The tanks are located inside the unit and additionally freeze protected by electric floorheating. They are all fitted with an ultrasonic tank sensor which is linked to the domotics system. The domotics system displays the real-time fill percentage of the tanks.

Each tank has its own ventilation. The grey water tank ventilation is fitted with a carbon filter. An active ventilation system with an air filter is installed on the black water tank. This active ventilation prevents unwanted odours and ensures that no chemicals are needed. This way the content of the black water tank stays 100% organic.