This looked like an ok thread to bump for this info.
I kept my asterinas for about a year letting them multiply without seeing anything that really bothered me.
They don't bother any of my zoas, and they might eat coralline, but even the hundred I estimate I have can't keep up with coralline growth if they eat it at all.
They do eat my purple hitchhiker sponges which isn't great, but not a huge deal, for a long time the sponges seemed to outgrow the predation, but now I think the asterina numbers are high enough that their activity is what is causing the significant decline in my sponge population.
They don't touch my photosynthetic sponge and the didn't touch my orange tree sponge until it died.
Today I saw this...
A few minutes later...
That is an asterina that peeled up the edge of a limpet snail and is eating it.
Limpets are so dang slow, even by snail standards, that I don't think any of my other snails are at risk, and the limpets never appear to do anything useful anyway, so keeping their pop down is fine with me, I used to remove them manually every once in a while.
But anyway, I'll begin occasional manual removal of the stars to drop their predation back down to unnoticeable levels.
