What is this white stringy stuff?

[SaltyGirlMom]

Please help ID this white stringy stuff that seemingly appeared overnight. I’ve been searching the net but I’m not seeing anything that looks exactly like it. Seems it’s attached on one end and the other sways with the water flow.

 

[papercrab]

Hydrozoas?

 

[Isaac Alves]

Could it be Spionid worms...like you see in this picture:

https://www.reef2reef.com/threads/spionid-worm.841856/

 

[papercrab]

Do they have kind of a hairy side or are they smooth. If its got kinda like cillia allong the side that might suggest digitate hydroids. If not id go with the latter suggestion of spionod worm

 

[SaltyGirlMom]

Thanks! Looks cilia-like. Doesn’t match those exactly tho.