Discovered small black worms in filter

[brewsterfl]

I have discovered small black worms in my filter. there are quite a few of them. probably had it for awhile and thought it was dried blood worms wet......I have clout. anyone know what kind of worm this is? first time having worms in aquariums.

thanks. I'm stuck on this one

 

[pyackel]

They sound like Tubifex worms. Were they alive? What is your water quality like? The reason I ask is that Tubifex worms inhabit muddy, polluted waters.