Hitchhiker starfish ID

[MHannon]

Found this in my sump, there are 2 of them.

Can anyone tell me what it is, and more importantly, is it reef safe?


Just a size comparison

Underside

Top

 

[MHannon]

I heard it may eat corals, but in its defense, it has been on the glass for almost 2 weeks, and appears to be grazing algae.

 

[greenbean36191]

It's an Asterina star. Most species are harmless, but a few will eat corals. The trouble is that there is no way to tell the difference between the two groups visually. Unless you have corals disappearing with these stars in the vicinity I wouldn't worry about them.

 

[MHannon]

Hmm, ok thanks. I dont have any corals in the sump, well a few kenya trees, but im not worried about them. I guess ill keep the starfish for now.