Flatworm?

[IndianaReef]

I took this guy out by direction of someone in another post saying it looked like a flatworm. Any idea now that we have a better look at him? He's quite firm and has curled up in a ball

 

[AlyciaMarie]

Looks more like some kind of Chiton to me. It seems a little big to be a flatworm. Did you take pictures while it was in the tank?

 

[ISpeakForTheSeas]

Yeah, that's a chiton - most likely an algae-eater.

 

[Crabs McJones]

Agree chiton