Coral Barnacles

[boilermaker1]

I see two of them on a newer acro in my tank. I did a little bit of googling around that they're just harmless filter feeders? If so, I'll leave them alone. Pics wont come out, but I saw them on the show "life" on the discovery channel... and I'm pretty sure on the ID.
Coral is colored up with polyps extended... looks like no harm, no foul, but let me know.