Fletch: Had a Yanmar class a month or so ago and we had an Algae-X in the class and got to take it apart. It is a waffer magnet
inside the plastic shell. Fuel passes over it
and the magnetic field changes the physical characteristics of the microscopic organism found in the fuel. Yanmar reps swear buy. I plan on getting one myself but it is an expensive magnet. Thought about trying to make something like it using the same principal but haven''t got around to it.
All I can say is that I have heard good thing about it. Good Luck
Fairwinds & Following Seas