I did have a problem once with getting Kero from an oil company with inground tanks.
I use 2 funnels when I filter my Kero into my flight jug. A fine fine mesh screen in a funnel and the Mr. Funnel. It had cloged both so many times with crap that I ended up just dumping the 5 gallons.
I now get it from the Local hardware store that has an above ground 250 gallon tank. I have no problems with them for the last year or two.