I have plenty in my tank and I actually given some out in the past to other members. They do not bother my corals nor do they do any harm. Dont believe everything you read especially on the internet. See for yourself from personal experience. A lot of memebers claim here that they see their corals going bad and automaically assume that they are the problem. I have them for years, have sps and other corals and they are not touching them. The come out at night and roam around the tank but i havent seem them kill none of my corals. So going back to if you should kill it, no dont its a safe star from my experience. But what you do with it is up to you. But before you kill it see if anyone wants it.