Rust looking crud in fuel filter

[Raptorrider2001]

Just finished changing the fuel filter after 12k miles (24k on truck). When I removed the WIF from the bottom of the filter, it had a large amount of rusty looking particles in the bottom of it. The last time I changed it, this was not the case. I held the filter upright and shook it and large amounts of this crud came out with fuel. I set it in a coffee can and poured some fuel through it and more came out. Is this the way it should be? I am not talking about small particles here. :confused:

[dmaxalliTech]

raptor, It may be alge, You might wanna try running a biocide additive and see whats happens.

[redneckcowdoctor]

Raptorrider2001, I've seen the exact same thing on several filter changes. Don't know what it is but it was somewhat disturbing (at least the filter caught it). I've go 103,000 on the truck and change the filter at 15,000. I get about half my fuel at back woods stations so maybe it is algae as maxalliTech suggests. I always thought of algae as green but I guess chlorophyll isn't real important if you're living in a dark diesel tank. Jeff

[mackin]

Water, just not in the free zone ...On it's way to the next stage .. Well, this is what I determined when it was discussed last time ... If I remember correctly ...

Every filter I cut open had some .

[Raptorrider2001]

According to Diesel Injection Service, if it is algae, it will be coal black. This is a red rusty color.