Starbrites Startron, should be available at local marine supply store and claims to dissolve the biofilms and rid the nasties without clogging filters. NAPA carries the same product and is called Xbee.

Understand that Hydrocarbon Utilizing Microbes must have water present in the fuel to live. Since you live in a high humidity enviroment, water contamination will always be a problem to deal with. You'll have decide wheather you want to disperse the water or coalese it. Then pick the appropriate additives to do it. Startron does claim to disperese water so you may only have to use one product. Which you will want to do on a regular basis.

HUM bugs; Black soft crud = Desulovibrio bacteria, Greenish crud =
Hormoconis resinae, orangeish stuff = Pseudomonas aeruginosa

If the stuff is hard it may be asphaltene agglomerations. Then you will definitly need to polish the fuel and change the strainer.

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47,000mi

04 VW TDI Passat 80,000mi
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