zoa and algae

I removed a good sized chunk of a chalice that had overgrown a rock with zoas. Once off I noticed this really weird sight. Looks like purple blob that has a deep hole in it and orange filament running through it and don’t know what it is ?!

I have this piece of rock, it is covered partially with zoas. They have been in my tank for some time, but what you can’t see is all the bubble algea all over this rock. It is starting to spread on the rock and affect the zoas. My question is. “Could I take this one rock out and do a hydrogen...