Where space is, or might become an issue, there is merit in installation of an underground water tank. It's no problem, but integrity of the unit is going to be vital. You do not want to have to dig it up. Tankworld has put intensive research and development to FRP underground tanks in which you may have strong confidence. You can choose tank and filter only, or upgrade to an inbuilt Davey submersible pump and wall-mounted RainBankr system for tank to toilet applications. Click the arrow right to browse through the range.