Help, What is this on my rock?

[illestj0rge23]

Can anyone tell me what this is on my rock, and is it good or bad?


http://community.webshots.com/mypho...D=212611737&photoID=426349461&security=mxqzZk
http://community.webshots.com/mypho...D=212611737&photoID=426350026&security=mZLMwN

 

[Fluff]

 

[steve-s]

Brown button polyps (aka Zoanthid sp.)

http://www.advancedaquarist.com/issues/feb2003/invert.htm

Cheers
Steve