Aiptasia?

[Mastertrcky]

I know the one on the right is but is the other one? It's just weird cause it has those white ball tips

 

[NarwhalLover3]

Pseudocorynactis

 

[Mastertrcky]

Any experience with them?

 

[NarwhalLover3]

Yep. They don't bother me but some people hate them. They are really slow growers from my experience, so your tank won't explode with them like it will with aiptasia. Really, it's up to you. You could feed it and display it (which will make it grow a little bit faster, but not much) , or nuke it. I like them and some varieties even sell for $100.00. Not all get very big. I don't think your variety will, only because mine haven't. Good luck! Hope I helped!