These Cylindrical Vertical Water Storage Tanks are made of food grade Polyethylene which makes it the most reliable water storage tanks. To increase the toughness of the tanks the company offers triple layer tanks with Inside white layer;with Intermediate Layer is of Red and outside is available in wide range to suit your requirements. The Outer layer is Ultra violet (UV) stabilized to mitigate harmful effects of sun rays and the inner White layer is safe to use for Potable Drinking water. These water storage tanks are round in shape to sustain Natural Weather conditions. These tanks durability of Water Storage Tanks is important as they will be with you for a very long time.