ID this for me please

[ASIN28]

Does anybody know what these are? I went from one, to them started to spread on the rock. Good or Bad?

 

[vetteguy53081]

These have a generic name:
Bright green oaly

 

[ASIN28]

These have a generic name:
Bright green oaly

Good or bad? Idk where they came from

 

[Sharkbait19]

Not harmful but they grow like weeds, may crowd out other corals so it’s best to keep them back or away from others.

 

[Gtinnel]

I think whether they are good or bad kinda depends on if you like them. They are just a fast growing palythoa.
I bought a frag of one head about 6 months ago and it is now probably 30 or so, but I've kept them contained to one rock.
If you decide to remove them be careful I'd suspect they contain palytoxin.