White stuff in hammer’s head turning brown

[accidental_reefer]

Hello, following a prior post , over the past week as the polyps receded within the hammer head, white stuff filled the gap left by the polyps up to the boundary of the remaining polyps (I saw no bailout so don’t know what happened to them). The white stuff, however, thereafter starting turning brown.

Does anybody know what is this gunk in the hammer?

Pics below from Tuesday, Saturday, and this morning to show progression and substance described. During the day the remaining polyps puff up and cover much of the gap (albeit in decreasing coverage) so took me a while to recognize this brown stuff filing out the skeleton.

Thanks.

 

[Newbiereefer98]

Personally it looks as though you have other thriving Euphyllia, I wouldn't keep this in my tank much longer at risk of it developing BDJ (brown jelly disease). Can't really comment on the white turning brown, to me just appears to be a hammer that didn't make it.