Acro pest? RTN/STN

[Dartolution]

Recently I have had a while acro that has been in the system for about 2 weeks or so suddenly start to RTN on one side, so I fragged it up, superglued it over the necrosis as best I could, rinsed and placed back in the tank.

I believe that the RTN is a result of a drop in ALK (which normally runs 9.0dKH), down to 7.2dKH.

However, upon inspection of a mariculture colony I have I noticed these tiny "brushes" sticking our of a few polyps... small, tiny, white sticks/brushes ...
This acro in particular hasn't had very much if any PE at all either...

Does anyone know what this could be? I only see a few of them ... hydroids? Im not sure...

 

[doctorwhoreefer]

Got any pics?

Did you dip the coral as well?

Do you feed plankton specifically, everyday?

 

[Piper27]

Maybe barnicles if they look like small fans that poke in and out of a small bump on the coral.

 

[Dartolution]

I don't have a camera capable of taking such a picture. Definitely NOT barnacles. I do have a while acro colony with one on it, these are not a barnacle.

They are tiny white sticks, maybe a millimeter in length, that look almost like feathers... very small and very inconspicuous.

This particular colony isn't growing or showing much or any PE at all. I have checked for signs of red bugs and AEFW to no avail... these brush things are the only thing on the tissue...

anyone else ever noticed anything like this?

 

[zangmann]

I have these on one of my SPS, I beleive they are Zanclea hydroids. They are reported to be commensal - living with, on, or in another, without injury to either.

Although the researchers describe Zanclea as a commensal symbiont in the wild, with less biodiversity to keep them in check in an aquarium we're taking the liberty of calling Zanclea a pest. If you've seen them before, you'll agree that anything that grows on a coral and detracts from how we want it to look is a pest "“ seriously, looks like a bunch of equally spaced stubble on the surface of an Acro, gross.

 

[Dartolution]

ZANGMANN!!! that is exactly it!

have you had issues? the PE on my maricultured colony is crap....

 

[zangmann]

Glad I could help Dartolution!

No problems with the hydroids, they haven't spread to other corals and the coral seems to be happy. PE and growth seem fine as well. It almost seems like the hydroids have been covered by new growth here, I don't see any in this picture from today:

They may be there but I can't see any and they don't seem to be bothering the coral enough to hinder growth/health in this situation.

Good luck with your piece, let me know if I can do anything to help.