ID please need for concern ?

[nsrogue]

This started growing a few weeks ago on a polyp rock, they look like little feather dusters
but they do not retract, does this need to be removed from the tank >?

 

[reef208]

Looks like hydroids. Yank that rock out next time you do a water change. Put the rock in the dirty water, scrub them off with a toothbrush, rinse the rock off in the dirty water, and toss it back in the tank. Repeat as needed.

 

[nsrogue]

Thanks