Current 28G NanoCube / Distant 180G Tank Build

[Blom]

So I was doing some night fishing in the tank to see how many bristle worms I could find when I noticed a little black a white snail cruising over my zoa's. A quick google search led me down the road of sundial snails, and their little trap door confirmed it. So pulled him out of the tank and noticed a couple wee little star fish, one with 5 legs and the other with 3. Asterina stars from what I can tell, but thats the end of the understanding. Ive read both views on this that they are harmless.... and that they eat zoas and maybe some sps. Just seeing if anyone else has any experience with them.