Found parasite ID

[Cammywammy]

I found this worm looking thing while changing water in my tank anyone know what it is? Also what are all the particles in the water seen in the pics?

 

[Hholly]

Could be a nematode. It's hard to tell what kind. Some are parasitic, some just eat crud in your gravel.

 

[Berylla]

I think its the crude in the gravel type.

 

[Wiggles24]

It looks like planaria to me