worms in filter pad!?

[bittersweet]

I didnt know exactly where to put this post, its not an emergency but I would like to get rid of it ASAP. I was cleaning my 10 gal community tank a few days ago and took the filter pad out to rinse some of the residue out to find hundreds of tiny dead black worms all over it! they are the size of blood worms..yet I do not feed my community tank bloodworms, and theres tons of them. Not too long ago (bout a month ago) I did a 95% water change and left all the gravel and everything in, but when I added new water I noticed these little hair like white worms squiggling around, I figured they were some sort of bacteria and I added salt. does anyone know where these worms in my filter pad came from or what they are? I dont see any in the tank alive..

 

[7chanaa]

is the tank a marine or freshwater tank

 

[canarsie11]

is the tank a marine or freshwater tank

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