Check that there is enough aggregate around your tank.
An exclusion zone of 20mm aggregate e.g. blue metal/stone (no clay/concrete) must be placed evenly around the base of the tank. This will stabilise the tank pad, prevent erosion and deter rodents. Erosion of the base will undermine the tank wall and bladder which in turn could cause the tank to fail. Therefore, it is important that the aggregate is drawing away any roof run off.
Aggregate should be at least 800mm from the base of tank and 75mm deep.
The recommended quantity of aggregate for each tank model is listed in the table below:
Tank Model | RT-25
RT-40 | RT-60
RT-80 | RT-100
RT-130 | RT-160
RT-200 | RT-230 | RT-275 | RT-310 | RT-365 |
Volume of Aggregate (20mm) required | 0.8m³ | 1.0m³ | 1.2m³ | 1.6m³ | 2.0m³ | 2.1m³ | 2.0m³ | 2.1m³ |
Do not use aggregate that may be contaminated or will be a catalyst for corrosion.