Fuel Additives & Preventing Diesel Bug

ANTI - BUG Fuel Additive

EXOCET are market leaders in fuel additives and have conducted various tests on a broad range of fuel grades and it is evident that microbial activity also know as the ‘Diesel Bug’ is on the rise.

What is the ‘Diesel Bug’?

Is any living micro-organism that can live, feed and proliferate in a diesel environment such as a storage tank. These include bacteria, fungi and algae to name a few. These micro-organisms thrive in warm surroundings and require hydrocarbon and water to excel and grow. They can quickly multiple and over run a fuel tank, manifesting themselves in the form of a slime or sludge like substance. This leads to decreased fuel quality, blocked fuel filters and in serious cases damage to engines. 

How does the ‘Diesel Bug’ Grow in fuel tanks?

These micro-organism’s can excel in older fuel tanks which may not have be cleaned in a long time, laid dormant for a period of time or contain a  build of  sludge at the bottom of the tank which can encourage the diesel bug to inhabit the environment. 

A partially filled tank left over time is susceptible to condensation build up on the inner walls when exposed to varying temperatures, which provides prime living conditions for the Diesel bug.

Diesel can contain a percentage of bio-fuel which is hygroscopic. Which means that it can attract and retain  water or moisture. The diesel bug can latch onto this and begin to grow and spread quickly. 

Research has found that the diesel bug can multiple by double every 20 minutes, this can lead to the diesel bug over running a tank very quickly. It can resemble a slime like sludge often black or dark in colour. 


How to tell if your tank has been contaminated by the diesel bug?

There are a few indications that your fuel may be contaminated with the diesel bug. It is important to address the problem as soon as possible, to prevent any damage to engines. 

  • Blocked filters more frequently than normal
  • Blocked pipework or ports
  • Increased steel fuel tank corrosion 
  • Sediment or sludge within the tank
  • Restricted fuel flow or pump starvation
  • Loss of engine power with contaminated fuel
  • Difficulty starting & maintaining smooth running
Anti Bug additive
blocked fuel filters

Eliminating the Diesel Bug

EXOCET Anti-Bug Fuel Additive is formulated and proven to both prevent & kill the diesel bug in diesel storage tanks, which ensures high fuel quality.

Protection – The additive can be used in a protective dosage ratio of 1:20,000 litres. This mixture ratio is tested and proven to eliminate the chances of the diesel bug inhabiting the fuel storage environment. This provides excellent peace of mind to ensure fuel quality is not compromised and perfect for use in storage tanks where fuel may be stored for long periods of time.

Kill – A higher dosage rate of 1:5,000 litres is used to kill any existing diesel bug that is already inhabiting the fuel storage tank. 

Both dosages cover a large spectrum and variety of micro-organisms such as bacteria, viruses, fungi and yeasts. The Anti-Bug additive has an immediate effect and provides full protection against not only the diesel bug but also tank corrosion. The clean up rate for this additive is 24 – 36 hours, providing a quick response time from the point of initial mixing.

Anti Bug is approved as a fuel additive by main engine manufactures such Mercedes Benz, DAF, MAN, NATO, Deutz, Shell & other reputable brands

How to Prevent Diesel Bug

As well as using the ANTI-BUG protective dosage there are a few other key preventative measures which can be taken to reduce the risk of the diesel bug. 

Regular tank maintenance such as inspections and cleaning can help ensure that the environment is clean and prevent the diesel bug from inhabiting the tank.

Ensuring that there is no risk of moisture or condensation entering the tank, this could be from an external source or from a build up on the inner walls of the tank due to changes in temperature. Ideally, a tank needs to be re-filled regularly utilising the space to prevent the inner walls from getting the chance to build up condensation due to temperature changes. 

Having a regular turn over of fuel is important, if a tank is left idle with diesel for a long period of time this gives the diesel bug a prime opportunity to thrive. For example many  boats or marine equipment are removed from service and stored over winter. If there is a fuel storage tank half full of fuel, this can give the diesel bug perfect living conditions and will cause problems once the boat is put back into service as the bug has been give months to multiple in size within the tank.


For more information on the diesel bug, additive & how to prevent it you can phone or email us and we will advise further on how to best deal with the problem on hand, based on your situation.

Exocet fuel additives

Buy Anti- Bug online from our online shop by clicking on the following link. 1 Litre treats 20,000 litres on a protective dosage or 5,000 litres on a kill dosage. Larger quantities are available on request. 

Talk to us about your Diesel pumps, Fuel management systems, Fuel Storage and Garage installation requirements today.