What is this?

[laura]

:unsure: I have noticed something growing out of my live rock. Since I am still new, I haven't a clue what this is. They pop in and out frequently. Can anyone help me?
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[laura]

Thanks! Do they grow much? These are currently about 1/2 inch in diameter when fully opened, and about that tall.

 

[curator]

I'm curious...these are always called feather dusters, however, one reference I looked at some time ago called them barnacles. Will some please clarify? Do barnacles look anything like a feather duster?

Thanks,

John

 

[curator]

Take a look:

>http://scribalterror.blogs.com/scribal_terror/images/2008/02/23/barnacle_2.jpg</a>

 

[curator]

Barbara:

I do notice that the "feathers" on a barnacle are not symetrical; the ones in my tank must be feather dusters since they are. I have a few that are dark blue...very nice!

 

[jmaneyapanda]

barnacles almost always have a rhythmic pulse to their filter feeding. The pull they tentacles in every second or so, and then put them back out. Feather dusters arent rhythmic. They pull in when disturbed, and otherwise stay out.

 

[notireef]

I have about 5 dark plum colored dusters on a piece of live rock and a few more on other pieces of LR. There are some red and white ones too.....cool to watch