[I had heard these guys can much on corals. However, I know I have some in my tank and have not seen them eating corals or any corals that look like they are suffering or been munched on. I figure I would leave them alone until I see some damage. Any other knowledge on these guys?]
[I have tons of these little guys - I only see them on the glass and rocks. They eat algae. If your coral has algae, I guess it would look like the stars were eating them. IMO, very beneficial to your tank.]
