I was thinking bad o-rings too, maybe.

 

cant be algae, tank was down about 2 or 3 months ago and it was perfect inside, not a drop of gum or nothin! and it moves every single day. my first guess was injector orings beucase of my horendous smoke in the mornings, so i will check it again after this tank of fuel and see if it changes. i just hate to pull the injectors AGAIN when there coming back out in a few months any how! i was talking to travis and he said his does the same thing just no were near the smoke mine has, so this mystery black fuel filter thing is getting annoying. but i changed the filter today and dang... peppiness is back and it spools quicker, no wonder i lost mileage and power lately LOL

 

What vehicle is it out of? ha I would drain the canister and fill it about half full of Diesel Klean and put the new filter back in. Did it a few times. Works great.