What is it"

[Shell]

some kind of star fish. Good or bad?

 

[nervousmonkey]

Asterina star. Good!

 

[Steve Maxwell]

Asterina starfish. Been a lot of posts on here lately about them. Some people say they are ok, some say they are bad as they can quickly overrun the tank. From what I've seen a slight majority of people say to get rid of them. I've never had them (that I've noticed) so my experience is limited to what I've read here on R2R.

 

[AdamNC]

I've got a ton of them in my tank and the only bad I've seem is they kill/eat my coralline algae. They haven't touched any of my coral, sps, lps or zoas. The largest one I have is about the size of a dime. Usually at water changes I try to suck out as many as I can easily reach.

 

[Kershaw]

I had a tank with thousands!! Only issue was I had to knock them off the glass every morning. Best thing about them is if you get enough you can get harliquen shrimp. They will eat them.

 

[BigKid4788]

I had them. Got tired of them so I bought a harliquen shrimp. While I had them they didn't hurt anything