The Harlequin Starfish is a beautiful and unusual creature. I placed one in my tank several months ago, and it has done very well ever since. What I found ironic was when the Harlequin Starfish and the Harlequin Shrimp gathered together. The shrimp is known to eat starfish (preferably Linkia, Chocolate Stars, and similar), but in this case there was no risk at all. Reef-safe.