How to assess oil tank condition

1. Check that the tank is level, both in length and width. If there are significant irregularities in the base, the inadequate level is obvious. For a more detailed check, you can use a normal construction level or, if you don't have one, install one of the many 'level' apps on your phone - they are extremely easy to use. Place the phone along one of the horizontal edges of the tank and you will see whether or not there is a level.

2. Visually inspect the bottom of the tank from all sides - the surface of the base should be larger than the footprint of the tank bottom in all directions. If this is not the case, your filled tank is under structural stress which will result in
a) Deformation of the tank
b) Formation of micro-cracks in the tank structure
c) The formation of large cracks, resulting in oil tank leakage.

3) Inspect the tank itself. A discoloured surface of the tank, especially on the structural edges, indicates that the tank structure has been stressed for a long time, the structure of the edges has been disturbed and the tank has lost its rigidity. This process causes deformation of the tank. The tank will usually already have micro-cracks, which will increase the risk of leakage each time the tank is refilled.
Visible cracks. On a worn tank, cracks often form at the top of the tank, and a routine inspection will help to identify them.