What Is This Thing?

[showjyr]

When i got my live rock about 2 weeks ago this thing had one little branch sticking up. Now it has several and seems to be growing pretty well.

Can anyone tell me what it is?

 

[dawhits]

Is it like a tube coming up off the lr? if so, maybe tubeworms or something similar? I've had them in my tank before, and one piece of lr I got was covered in little white tubes like that.

 

[sophos9]

Looks like seaweed...

 

[ostrow]

The photos are rather blurry but from what I can tell it appears to be a form of caulerpa, a macro algae. It is generally a good idea to get that stuff out of your display. Many (not I) keep it in their refugiums. I prefer chaetomorpha as it tends to be less unruly than the caulerpas.

 

[joecoral]

i agree, it seems to be some form of macro algae (caulerpa i think?)