I believe they are detritus worms...Harmless but they large water changes should be performes as a large worm die off can hurt fish.
http://www.fish-as-pets.com/2007/11/planaria-detritus-internet-answers.html
Thanks!! U are such a saviour!! Frm the link u gave, I now strongly believe its detritus.. the pic in the link is exactly what im seeing in my tank.
Must be the damn new bio sponge filter im trying out.. I am so going to dumb those away and change them back to my regular sponge filters.
Thanks a million!!!
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