In the ongoing battle against bacteria in diesel fuel I've taken to keeping my tanks empty. This, after pumping out/disposing of 60 gal of old diesel that looked like bad coffee even after keeping up with a biocide treatment.  I've removed my tanks and had them steam cleaned once already and I really don't want to do it again.

A discussion with a fuel expert offered this: "Biocides are designed to kill bacteria when still in planktonic form (individual bacteria floating in the fuel) and not once they settle into a biofilm which resides on the walls of the fuel tank. When people have a filter failure due to plugging, this is when the biofilm (sludge) is at a mature stage when it begins to slough throughout the fuel. Dosing at this stage can be problematic yet present itself as helping. It can result in a dead mass in the bottom of the tank but can also lead to the proliferation of anaerobic bacteria under that mass which excrete acids. As the biocide is depleted it may also become a food source for the bacteria which creates a bigger problem.

There are more effective methods today that have been developed over the past couple of decades which are more suitable for this application and are non-biocidal in design. Fuel Right is a chemistry that interrupts the biofilm development and can dissolve existing biofilms. I use it in my Tartan and used it in my Aloha. It cleaned out both tanks - I had to replace a couple of filters but my fuel was clean from that point forward. Continuous use will prevent further biofilm development and the nice thing is, it is not a biocide."

Anyone familiar with this product?  http://www.fuelright.com/