Cant Identify this slug / worm thing?

[DAWREEFER]

Hello, I just want to know if I should be worried about this guy and if 'you see one there all lots' kind of mentality. I looked quite a bit and did not come up with anything. Please let me know!

 

[sixty_reefer]

That’s a nudibranch hard to tell which one

 

[DAWREEFER]

That’s a nudibranch hard to tell which one

harmful?

 

[sixty_reefer]

It depends most won’t survive in a reef tank due to their food not being well known, any chance of a more close up picture?

 

[sixty_reefer]

It looks a bit like joruna parva

 

[DAWREEFER]

It depends most won’t survive in a reef tank due to their food not being well known, any chance of a more close up picture?

He's so small I can't find him now, but he's white with black spots and antennas

 

[sixty_reefer]

He's so small I can't find him now, but he's white with black spots and antennas

That goes with the description of joruna parva try and google it