If your water pressure is not sufficient or subjected to frequent water shortages, use the S-lon PE+ Sump Tank as a back-up underground water storage solution. You can pump water to your overhead tank from the S-lon PE+ Sump Tank. This is useful mainly when the water pressure is not sufficient to fill the overhead tank. The tank design is unique to PE+ and withstands the ground pressure. S-lon PE+ Sump Tank comes with an inner white layer enabling to check the purity of water. It is available in 1000l and 2000l capacities.