ok for the ids first thing I would guess it is a copod cant be sure without pics

the second I would have to guess bristle worm again cant be sure without pics

and lastly kill the glass anemone they will kill any corals and several other things in the tank
easy way to kill glass nems is take a dosing seringe and a coffee cup full or water as hot as you can get it (without burning yourself) suck the near boiling water into the seringe and burn the glass nem it will literaly melt away