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Light oil tanks must be protected against corrosion, as the fuels such as gasoline and diesel stored in them are highly corrosive, and the risk of corrosion exists throughout the entire operational life of the tanks. Whether anti-corrosion is needed is not a \"choice\" but a mandatory safety measure. According to industry practices and technical standards, the following situations clearly indicate the need for anti-corrosion measures in light oil tanks: The properties of the stored medium determine that sulfur compounds, organic acids, moisture, and additives (such as tetraethyl lead) present in light oils (such as gasoline and diesel) can cause electrochemical corrosion of metals, with the most severe corrosion occurring at the gas-liquid interface and at the bottom of the tank. Water-phase deposition occurs: free water often accumulates at the bottom of oil tanks, and the chlorides and acidic substances dissolved in this water form an electrolyte, leading to severe electrochemical corrosion and bacterial corrosion (such as by sulfate-reducing bacteria) on the tank bottom and lower walls. The tank roof and inner walls are exposed to a corrosive environment: water vapor, oxygen, and volatile hydrogen sulfide in the gas space inside the tank condense into corrosive liquid films when temperatures change, causing electrochemical corrosion of the tank roof and the upper inner walls. Signs of corrosion are already present: If inspections reveal thinning of the tank walls, pitting, peeling of the coating, or cracks at the welds, it indicates that corrosion has occurred, and anti-corrosion repair measures must be taken immediately. No cathodic protection or coating protection has been applied: If the storage tank is not equipped with a sacrificial anode or a impressed current cathodic protection system, nor is it coated with an antistatic corrosion-resistant coating, it lacks basic corrosion resistance and must be enhanced.