What is this in my rock?

[mc12301]

Hey guys. A couple weeks ago I relocated my FOWLR to a new house. After it was all set up I noticed some growth on my live rock. They look like little tiny pink flowers with white polyps. There's about 20-30 of them. They look kinda cool but I'm wondering...

a) what are they?
b) are they safe for the tank and fish
c) could they spread like wildfire and take over? If so how do I prevent that?

I attached pictures.

As a side note, I've always had a broken keeping my sand end clean so when I moved the tank, I switched over to a custom cutting board bottom and it's awesome!

 

[mc12301]

I Meant... Always had a tough time keeping my sand bed clean. Sorry! Can't type today.

 

[billdogg]

The common name is Ball Anemone, although they are not really anemones.

Courtesy of Wikipedia:

Pseudocorynactis is a genus of anthozoans similar in appearance to sea anemones and in body format to scleractinian stony corals. These animals are cnidarians in the family Corallimorphidae.


Generally harmless, although they can spread and some have been known to sting nearby corals

hth

 

[JUNBUG361]

Look like baby aptiasia, then again I could be wrong

 

[Jakermelon]

Def think they are ball anemones like billdogg said

 

[johnike]

Bill would be correct, certainly not Aiptasia.