Urchin ID Please

[Seepu]

This guy is about 1 1/2 inch across.

TIA

 

[Hara]

looks like a type of pincushion urchin to me

 

[Seepu]

Are they as bad as I have read, regarding bumping rocks out of place?

 

[Hara]

If your rocks are really unstable, yes...mine are not secured with anything other than wedging and gravity and the urchins (3 in 3 different tanks) do not move them.

 

[Seepu]

They arent stacked too loosely, but I will definately give them a wiggle check.