Algae ID - Cymopolia?

[Who.Me?]

Does anyone know what this macro algae is? It grows out of my live rock as bright green stalks that resemble gerkins / baby cucumbers. They have a hard/firm texture and can be snapped.
Typically; I've notice them when they've reached about 10mm long and 2mm diameter, but I just picked one stalk off that was about 25mm long and 4mm diameter. It had started to turn white at is base.
I did a bit of googling and the closest that I found was Cymopolia Barbata, but that seems to have segmented stalks. I've not let this stuff grow, so I don't know if it eventually segments. When I remove them they are a single piece.
I've currently got a dose of ReefHD (flucanazole) in the tank that has taken care of a horrible case of GHA, Bryopsis and Caluerpa that I couldn't get rid of. This algae and a little red algae are the only two that seem to be resistant to it.
The stuff just spontaneously appears out of the rock.
Any ideas what it is?

Sorry about the rubbish pictures. I cropped these out of bigger pictures, because I've already plucked the latest examples off the rock and flushed them.

...

 

[blaxsun]

It's not GHA, but I can't identify it. Maybe someone else with sharper eyes...?

 

[bushdoc]

Following, have same in one of my smaller tanks.

 

[Who.Me?]

A bit more googling led me back here eventually. Looks like it may be either Nemoeris or Bornetella... https://www.reef2reef.com/threads/what-is-this.888246/

I'm leaning toward Neomeris, because the bigger one I removed this morning had a white base like the one in the picture in the above link.

Is it a pest, or worth leaving alone? I found another one this afternoon.

 

[ISpeakForTheSeas]

A bit more googling led me back here eventually. Looks like it may be either Nemoeris or Bornetella... https://www.reef2reef.com/threads/what-is-this.888246/

I'm leaning toward Neomeris, because the bigger one I removed this morning had a white base like the one in the picture in the above link.

Is it a pest, or worth leaving alone? I found another one this afternoon.

I'll agree that I can't tell for sure from the pics, but I'm leaning toward Neomeris too.

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/

 

[bushdoc]

Bingo! Thanks guys for ID!
It grows like crazy in my two smaller tanks, consumes Calcium and by the power invested in me by evil spirits I officially declare it semi pest.
I also declare myself as a supreme grower of rare algae, which usually dies in captivity
Seriously-it grows like crazy in my tank, but it is not cyano or Dinos.
I am actually taking all rock out of my 30 gal tank next week and putting new Tampa Bay Live Rock and starting new gorgonian tank.
Farwell Neomeris! I will not miss you!