Please help me ID this hitchhiker.

[RhinoChaser]

ive seen this creature crawling around my glass for the last few months. Not sure what it is. Anyone know? Should I evict it?

 

[Saveafish]

Medusa worm. Safe.
https://www.saltwaterfish.com/product-medusa-worm

 

[KJ]

Synaptidae cucumber.

 

[RhinoChaser]

Googled images of the Synaptid look a lot bigger. Am i to assume it’s going to grow a lot bigger?