What coral is this?

That will all come back to life. Give it about 2 weeks and it will be real nice again. The anthelia I find to want a little more light than what its going to get at the bottom of your PC lighted tank.

 

bc it's invasive.

 

what do you mean invasive? Sorry

 

+1 on throwing it away. I can't get rid of the button polyps. Once they got inmy tank, they just started sprouting up everywhere. also xenia is a risk. It can do the smae thing. I mean if you like them and want fast growth in your tank then cool, but once they're in... it's really hard to eliminate them down the line.

 

what Peredhil means is that the Anthellia or Xenia grows very rapidly under reasonable conditions and can smother other corals and quickly take over the whole tank - if it gets damaged , bits broken off by activity of snails or hermits etc it can start a new colony where the bits end up

I have 5 small colonies in my 5ft - only purchased 1 small rock of Anthellia

every week at water change time, I turn of all water movement, let tank settle, go in with nail scissors, prune the edges of the colonies and then syphon up the bits that I cut off
I run carbon 24/7 so dont have much concern over the little bit of pruning I am doing on a weekly basis.

I will get eventually get bored doing that and will possibly end up kalk pasting over the lot of them to get rid of them

Steve