Hair thin black worm ID?

[Rakie]

This is not my picture, they are faaar too small for my phone to take a picture of


Tank is finished cycling, and has a clean up crew only, otherwise these guys *seem* harmless.. My micro brittle stars scare the hell out of them, they live in the rocks and sand and don't have any trouble with my snails or micro stars.

They're absolutely tiny, thin as hair and 2-4mm in length -- I don't want to find out way too late that these little guys love munching on Corals or something.

 

[Umbra]

Look like a tiny nemertean (ribbon worm), might still be juveniles that could grow. Harmless to corals but are predators on other small inverts - some of the larger species can eat fish.

 

[Rakie]

What might eat them? I was thinking of getting a Sixline Wrasse

 

[Umbra]

Wrasses will likely eat them, especially at that size.

 

[mikeabuoy]

but a sixline wrasse is pretty much a :uzi: to all your other fish though