Please Identify this White Creature

[sydcam24]

Hi. I'm new to saltwater aquariums. Can someone please tell me what this white creature is with two antennas? Should I remove it? Also I'm noticing white things on my urchin and am not sure what they are/what I should do about it. Thanks in advance!

 

[HankstankXXL750]

The white things on your urchin look like flat worms maybe, I’m not sure about the other creature. Does it have a shell, or is it all soft. Here is a web site I have saved for hitchhiker identification.

Reef Tank Hitchhiker ID · Saltwateraquarist.com

Some reef tank hitchhikers are good, while others are bad or neither. Here is a reef tank hitchhiker ID list for the most common hitchhikers.

saltwateraquarist.com