Help ID?

[Ancarol2421]

Hi friends! I’m taking care of this tank at school. Was wondering if anyone knew what these are? Look like some form of anemone but I’m not sure. They’ve pretty much taken over this tank. Thanks in advance!

 

[Ancarol2421]

Some more photos. There are a few growing on the toadstool/leather at the base where it meets the rock.

 

[BlennyTime]

It looks like yellow polyp coral