Algae?

[Porkpie5000]

They look like a cross between a feather duster and some kind of algae. I don't think I have seen them before.

 

[WV Reefer]

15 minutes ago, Porkpie5000 said:

They look like a cross between a feather duster and some kind of algae. I don't think I have seen them before.

 

 

Could it be colonial hydroids?— It’s really hard to see the structure clearly in that pic. 

[Porkpie5000]

9 minutes ago, WV Reefer said:

 

Could it be colonial hydroids?— It’s really hard to see the structure clearly in that pic. 

 

Maybe? But I don't think so. At least not comparing them to pictures I can find of colonial hydroids. I'll try to get a better shot of them.

 

[Porkpie5000]

Does this video make them any clearer?

 

 

[Porkpie5000]

Most of them have a fluffy feathery top on them. A few have that more "structured" looking top. I don't know if that becomes the feather top eventually, but that's what I assume.

[mcarroll]

Pretty sure it is a type of green algae....name is escaping me though.   

 

The feathery things at the tops make it unusual though, at least in my recollection.  Possibly a tuft of cyano waving around?  (The pics of the tops aren't too clear so hard for me to say with any certainty.  Shutting off the flow so everything comes to a stop before you take the pic will give you and us better photos.)

 

I've never seen this stuff spread out of control (if it's what I think), but as with any algae, you should act in your role as #1 cleanup crew member and remove it if it seems to be spreading a lot.

[Joevember]

Looks like it could be codium or neomeris ammulata. Weird about the tops tho.

[mcarroll]

Neomeris!!!  That's it.

 

http://cfb.unh.edu/phycokey/Choices/Chlorophyceae/siphonous_greens/Dasycladales/NEOMERIS/Neomeris_Image_page.htm