[coolshot]

Recently, I bought a B & W UV filter. When i got home, after doing testing with the filter, I clean up my camera and so as well clean the filter. However, after I use my len cleaning cloth to wipe it, I saw a line of mark on the filter, about 7mm. So I tried to wipe it to see if can remove it, but still there. I've already make sure there was no dust on the filter and the cloth is clean. The mark does not appear to be a scratch.
I would like to ask anyone's expert advise what should I use to try to remove it. Will those lens cleaning fluid work? I really want to remove it, because if I take photos with some sun light, the photos will have a line on the photos.
Thanks.