I just noticed some of these in my tank and seemed like I remembered that they are bad. I looked on one site that claims they are not, would really appreciate some opinions on this. After I noticed the one I started looking close and have tweezed about 15 out so far and still notice a few more. Thanks for your reply in advance.
asterina starfish
- Thread starter beashay
- Start date
LeslieH
Premium Member
There's 26 genera and many more species in the family Asterinidae. Even the genera require a specialist to tell them apart so you can imagine how hard it is to distinguish the various species of small asexually reproductive stars. Just on gross differences in appearance there seems to be several species showing up in tanks. The vast majority of animals are mild mannered grazers but there are a few that do feed on corals. Awhile ago I looked at a year's worth of posts/pics here on RC & elsewhere to see if there's a consistent difference. In general the very small white or cream colored ones are harmless. Coral & zoa eaters tend to be larger & have different colored mottling (orange, red, black, brown, gray, blue, green). Not every colored asterinid is dangerous mind you, but those are the ones to keep an eye on.
reefnetworth
Premium Member
i lucked -out and got the white ones, and they do some serious algae eating. i first saw one on a piece of LR w/coral from my LFS. researched if it was reef safe, 1.7 years later i now have probably 100 of them, give or take a few. they cover the glass at night and graze better than any snail ive ever had! 
JDM
JDM
Avi
Premium Member
So far, the only downside I've seen to the small gray/cream colored ones that I have had for a few years in my reef, is that they multiply like crazy. They are avid algae eaters and leave a trail on the algae on the glass that they get to before I do, showing that they do consume it.
