Hey what is the stuff that can "grow in your tank and clog your filter"....

How do you know if you have it.. i was reading about some BIOCIDE stuff or something that supposedly takes care odf it but how do you know if you got it...

I change my filter pretty regularly and its always black like carbon deposits on my fuel filter or something.......

 

Diesel algae looks like brown snot on your filter, very obvious. It takes water in the fuel for it to grow as it lives on the fuel water interface. Most people will never need to use a biocide. Even if you do have an algae problem just biocide isn't the cure as their dead bodies will also plug filters, it's best to drain the tank and flush it then use biocide.
The black you see on your filter is asphaltines, a normal constituent of all diesel fuel.

 

Are you talking algea as in the stuff growing in a swimming pool or pond? (Different species i'm sure). How can anything live in diesel fuel. Isn't mother nature wonderful!

 

Actually it's a bacteria but people have called it algae for as long as I can remember. Algae need sunlight as they are a plant.
Still pretty amazing that something can live in diesel fuel.
They also have bacteria that "eat" petroleum products, they're used to clean up spills.