Algae
 

Do any of the diesel additives contain algaecide such as diesel kleen or stanadyne? I want to prevent algae in my fuel tank. If I have algae in my tank and I add an algaecide to my fuel do I have to worry about the dead algae clogging my fuel filter?[duhhh]

No. The so called algae are actually bacteria that live at the water diesel interface. No water, no "algae." If there is enough of it, it will clog your filter living or dead. The biocide stops it from growing.