Weird hard shelled critter. Slug like

[samuel venner]

I’ve just discovered this weird critter on a rock. It was latched onto it super tight so I unfortunately crushed it to remove it off said rock. Looked like one of those centipedes that roll up into a ball on land but in the water.
Any ideas ??

 

[Sisterlimonpot]

Chiton. harmless, great addition to clean up crew

 

[samuel venner]

Chiton. harmless, great addition to clean up crew

Thank you . Guess I won’t worry about the other 3/4 I’ve just found then

 

[OrionN]

It was a Chiton, unlikely that it will survive. Chiton are actually very neat animals. There is a species of small chiton that can reproduce in our tank, they are pinkish and only grew to about 1/4 inch or so.