Despite the fact that there are over 260 types of bacteria and fungi there is only several bugs that can live and grow in fuels and oils

In the interface between fuel and water microorganisms live In the water, they feed and grow on fuel oils and water in the bottoms of tanks.

The equipment that uses contaminated fuel is not only hazardous to the engine but also creates and inefficient power plant. Filters and lines are clogged by bugs and the by-products contain acid which can aid in fuel tanks too corrode and rubber hoses and seals deform and leak. Expensive equipment fuel pumps are subjected to increased wear and Injector deposits can lead to engine misfires. The worst case is you engine may stop at the worst possible time while at sea or when your emergency power generator is required to run.

Since even the smallest Nano level of contamination can cause these problems listed above so you really need to test your fuel on a regular basis.

The HumBug kit is designed to detect microbes in your diesel fuel, the detection results are either positive or negative so the kit is simple to use and takes 24 to 48 hours to confirm a positive or negative result.

It the result is positive for the existence of these bugs this indicates to the user if he needs to treat the fuel with a biocide or not. By detecting an infestation early and treating it, the size of the infestation can be limited and nulled in most situations.

Download the HumBug test kit user guide here

  • Take a sample of fuel from the bottom of your tank.
  • Remove the test cap’s center seal by peeling it back, do not to touch the rubber cap.
  • Draw sample from the fuel with the syringe.
  • Remove more than one CC / ML of fuel from your sample. Expel any air bubbles and excess fuel above one CC  / ML on the syringe and inject the fuel into the test bottle.
  • Replace the needle guard, and dispose of syringe in a safe manner.
  • Shake the test bottle vigorously for 1 minute and return it to the tube box and install the caps.
  • For 24 to 48 hours, place the tube box in a dark spot as bugs love to replicate with the lights off 🙂
  • In the case of active microbial growth within the 24 to 48 hours incubation period the test bottle bottom should turn pink or red to indicate a positive result.

Treatment of a positive result will require the use of an additive from the Biobor range of products.


  • Good for bug detection in diesel fuel
  • Quick results in 24 to 48 hours
  • Easy to use



We do recommend the HumBug test kit for bacterial only testing, you can view our alternative fuel bug test kits here or our bug, water and quality tests here.