[hheynow]

Seems I have algae in my tank. The pre-filter gets covered in a black film in a couple of hundred miles of driving which is wrong. This continually restricts fuel supply. I have been changing them continually. I decided to dose the tank with a biocide (FPPF Killem) the other day. I still see a black film forming on the pre-filter interior screen. I thought the biocide kills the algae preventing it from "sticking" to mesh? I guess it's NOT like shocking a swimming pool with chlorine. Will the dead algae from the tank eventually make it to the pre-filter in non-clinging chunks which can be removed by changing the pre-filter? I have had the tank screen out which did have a covering of algae so I replaced it, but that was two months ago.

 

[240_benz]

The biocide may be killing the algae but it's still in there so it's probably just floating around clogging the filter. The purpose biocide is to prevent algae from forming in the first place.

 

[Rmac58]

Sounds like you had a quite a bit of the stuff, but yeah, it'll eventually get all the crud out.

 

[mrbenz7]

Have you recently switched from Diesel to Biodiesel? This happens when you make the switch and every Mercedes Benz Diesel owner, including me, has had to clean the screen and keep a few filters in the trunk for this purpose. The nice thing is that this stops eventually when all the algae runs out, it's just a pain until then.:thumbsup:

 

[hheynow]

Bought the car last August and ran B99 exclusively until winter when I switched to B20. Since it's warmer these days I'll go back to B99 for a few tank fulls and will continue to dose each tank with the biocide. I have spare pre-filters since I believe I'll be changing them for a while longer.

 

[hheynow]

Update
The biocide has killed the algae and now it's being brought up to the pre-filter in black sand like chunks. It no longer sticks to the pre-filter screen. When I see a bunch of it in there I gently tap the pre-filter and it drops to the bottom. Then I disconnect the fuel in side and the chunks fall out leaving the screen totally clean. I expect to have to do this for a while but that's OK. At least I'm not going through pre-filters every week like before. Killem FPPF is great stuff but extremely toxic.

 

[Gregs300CD]

I think Startron is supposed to eat the stuff up without that problem. Can't say for sure though, because I've only used Biobor as preventative.