What is this? One on chalice, one on acan...???

[DothanReefer]

I've noticed a couple of these things over the past few weeks. I have no idea what they are? They haven't gotten any larger and don't seem to be bothering the corals (yet). Does anyone know what these are?

Video here: YouTube vid of chalice

 

[KJ]

Hard to tell from the pic. Google Digitate hydroids.