Tiny starfish? Are these good or bad?

[ThRoewer]

I'm going to disagree with most posts here.............I hate them and they're a detriment as they can easily decimate all coraline growth, which allows other pest algae to take hold.

Yes, I went through that as well and have to agree that they can create settlement space for nuisance algae. But my 4 diadema urchins are by far tougher on the coralline and on top of that reduce my live rock to fine silt.

But coralline alone is no protection from nuisance algae if you have excess nutrients...