Most fuel-burning tanks need some kind of filtration system in place to purify the fuel supply and reduce as much excess pollution as possible. For diesel tank filters, this is mainly achieved by separating the diesel emulsion from water. It’s very easy for oil, petrol, diesel and other fuel containers to become dirtied by contaminants if they are not properly stored and filtered regularly. It’s important for the fuel itself to be well maintained, which a good filtration system should help to provide. Some diesel filters come with translucent parts that allow you to see how much water is building up in your diesel supply.