What is this!?

[sereneabe]

After buying live rock and setting up a pico reef, ive found a few hitchikers that i had a faint idea oftheir species. But today, anout 2 weeks after setup, this new guy showed up (see below).

Ive also attached a picture of a feather duster and an anemone that any information regarding them would be appreciated. Im mostly curious about the star-ish translucent things in the first picture.

Thanks!!