Red worms - anyone that can I.D.

Hey just got a bit behind on filter maintenance and pulled out my filter socks to see a few lumps stuck on the outside. The biggest lump 2cm. They are red lumps and made up of 1000's or 1000000's of tiny red worms. Worms look to be about 1cm long and not much thicker than a hair. Picture included of the lumps.
Anyone got an idea of their type and or origin and any threat level they may present?



Cheers

You will often find little worms that live in the substrate or in the filter media of your tanks. They are generally harmless and or normally a type of round worm that feeds on detritus. The fact that they are in such high number in your filter sock is no surprise as a) that is where they will get caught after they are stirred up out of the gravel and b) that is where the good detritus hangs out.

I actually view them as part of a healthy tank

Yeah its just unusual they are in the outside of the sock and in such tight groups