Sea slug?

[Hunter1036]

This looks like a super thin slug but it looks like coraline algae yet I see it move very slowly. Anyone know what it is and if it’s good or bad?

 

[Hunter1036]

 

[Maritimer]

Looks like a flatworm to me.

This isn't the usual "ghost" variety, and some of these guys can be very carnivorous. I'd be tempted to leave that guy out of my tank, were I in your shoes.

~Bruce

 

[ReefQueen]

I agree with Bruce.

 

[sfin52]

Agree with both I do. Remove from tank I would.