Fuel that is infected with bacteria is not reliable. Filters clog prematurely, creating flow restrictions and ultimately total blockages. Gauges and other sensitive in-line instruments such as flow meters become faulty. Corrosive acids carried through the fuel system can cause expensive damage to injectors, pumps, fuel tanks and hoses.
Performance suffers, and maintenance costs are elevated.
But perhaps the most critical concern is the potential for blockages causing total engine failure while underway. The sea is unforgiving, and this situation can have devastating results. This is particularly true in foul weather, where a good sea can stir up the growth in a fuel tank and cause rapid filter plugging. Until recently, biocide dosing was the common method used to control microorganisms in fuel oil. There are many brands of biocides available for diesel fuel treatment, but they are all composed of highly toxic chemicals.