uknown strings on my tank, what is this?

[rafaelpty20]

Is not a baby serpent sea star, do someone have this before?

https://youtu.be/vM_F1VnhuJo

 

[rafaelpty20]

 

[ericarenee]

spaghetti worm perfectly safe

Not quite the same about that aiptasia peeking off the edge thou

 

[BlueMoonFox]

Agreed. Though, looks like aptasia on the other side...