We advise to preserve the life of your steel fuel tank and protect it from the weather, that you carry out tank maintenance annually.
Top tips for your annual inspection and maintenance:
Remove any overgrown vegetation from around the tank
Check for any signs of a leak by looking at the ground below and around the tank and oil line/filter. There may be a darker surface or you may be able to smell fuel.
Check that the tank base and piers are all solid and not subsiding or cracking.
Lightly sand off any surface rust with fine sand paper.
Make sure the tank is clean and dry, and that the weather is going to remain dry too.
Treat and paint the tank and also the underside if you can reach it with an exterior metal paint. Using a roller gives a better coverage.
Example below of this tank, before and after its annual maintenance.