Anemone-looking corals? Help identify and prevent them from taking over...

[Jesse Sunday]

Hi all! It's been a while since I've been here.

My 32 BioCube is just over a year old and these things have been in a race with the Encrusting Gorgonians (Green Star Polyps?) to take over my rocks... can someone give me an idea of what they are, and more importantly, how I can prevent them from taking over all my rocks?

The only open spots on my rocks are now where the BTA are attached.

They look like brown/purple anemones that stick onto rocks, glass, or anything they can. :)

Help! :)

 

[twentyleagues]

I would say its a ball anemone or a majano. Been a while since ive seen them they usually look greener..... Do they fluoresce under blue light?