Help ID what this is


Premium Member
 I got this frag and I noticed there's this black thing on the bottom of the sps. It seems to be growing in size as well as the coral looks darker.The first photo is from Nov 22 and rest 2 are from today. View attachment 6591
Is it soft? Maybe a dark sponge?If worried about it, you could smother with some of that epoxy putty your using along the base to cover it.
If you're concerned, you may cover it with some of the epoxy putty you're applying along the foundation.
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