Hydroids (digitate specifically)

[alexytman]

How harmful are they? How badly do they sting. If so, do they sting humans?

If removal is needed, what should I do?
If removal is not needed. They're pretty dang cool

 

[Crabs McJones]

How harmful are they? How badly do they sting. If so, do they sting humans?

If removal is needed, what should I do?
If removal is not needed. They're pretty dang cool

I have one or two in my tank, they don't seem to bother anything, but they're not near any coral. From my understanding if a coral does get near them or they decide to anchor down by a coral they can harm it. I've never touched one though to know if they'll sting humans.