Dont know what this is? Maybe a starfish

[Gza166]

My daughter noticed it on the glass and it's no bigger then a fingernail of a pinky.

 

[Flreefer]

Looks like a Hydroid.

 

[Gza166]

Bad? And if so how do I get rid of it

 

[Flreefer]

Don't really know much about them, to be honest. To the best of my knowledge, they aren't good. I would google it, and see what pops up. I think they are basically a type of jellyfish, which can sting corals and are free floating. Unfortunately, if you have one, you've probably got more...
I've seen them on the site before, but I've never read the best course of action.
Sorry I can't help more! Good luck!

 

[Gza166]

I could only see one but I did my water change and I just sucked him up. Didn't wan to chance it.