I have never heard on this site or others that IF the algae gets really bad, you have to pull the IP. If an algae attack gets bad, the filters plug up before anything else AND the engine stops running. To get rid of algae (I have to assume its algae and not "sludge") you need a biocide, which is a liquid that kills algae. Very common on diesel marine engines. Biobor works. I use a product called BioCide made by Racor. Biocides are generally available at really good marine supply stores. (this Racor Biocide is so poisoneous they can't ship via UPS).

Algae will plug the 2 fuel filters. The small white (or clear) one before the round canister main filter. Keep plugging away (excuse pun) at using the biocide, keep several of the pre-filters in your trunk and a screwdriver to replace the filters before you drive down to LA. Plugged fuel filters feel like you are running out of power at the higher RPM's. Generally the engine will idle OK (not much fuel used ideling).

Like Sixto said, if the "attack" is really bad, you'll need to pull the fuel tank. Take it to a real good radiator shop and have it boiled out. Clean the fuel sending unit out with brake cleaner. I think DMorrison posted a fuel tank pull and clean post about 4 days ago.

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84 300DT Puke Yellow. Totalled after 438,000
84 300DT Orient Red. 169,000 (actual mileage may vary)
2002 Explorer EB (wife's)