Predator Starfish

[SRT80]

My brother has noticed he has the Predator SPS eating starfish seen here...

http://www.garf.org/news26p2.html

Scroll down til you see "Spontaneous Division...starfish that is a coral predator". I haven't seen them, but he said they look exactly like that and are spreading. He doesn't have any SPS in his tank though. He has stuff like zoas, mushrooms, yellow polyps, green star polyps, xenia, etc. And one huge frogspawn. Everything seems fine but I haven't been able to find any info if they eat any other coral. All his seem fine though. Anyone know a little more on these? When he sees them on the glass should he toss them?

Also, he said he noticed what looks like a baby brittle star about the size of a quarter and only 7 legs. Does anyone know about that...bad or good?

Thanks,
Steve

 

[crumbletop]

I've heard conflicting things about those starfish. The ones in the article you link (GARF) that are pictured as eating corals have legs that are all the same length. I have had one starfish like that that was eating an acro. I also have many Asterina starfish (at least that is what they look like to me) that don't change morphology (i.e. they don't turn into regular 5 legged starfish, but always have a few short nubby legs). These I don't have a problem with at all. Anthony Calfo mentions them in this article:

http://www.reefkeeping.com/issues/2004-06/ac/feature/index.php

Basically, it sounds like if there isn't enough food around, they'll eat what is available. So it isn't necessarily reef safe, or "harmful". Probably not anything to worry about -- but could be. How's that for a definite answer