What are these stalked green sprouts?

[BleachedCoral]

These are sturdy, slow-growing sprouts that kind of look like leeks. What are these strange sprouts? Thanks for any help.

 

[ISpeakForTheSeas]

Neomeris algae:

Neomeris sp. This is a rare calcified green macroalgae that usually dies out in captivity. However, it has a rare chance to go invasive. Since it is calcified, I would assume few organisms could consume it besides urchins.
https://www.marineplantbook.com/marinebookneomeris.htm
https://www.reef2reef.com/threads/neomeris-annulata-reboot-only-option.279012/

 

[ReefRondo]

Neomeris annulata