Weird thing on hammer coral

[Jé123]

Does anyone know what this thing is? Sorry for the bad quality of the pictures (I did my best :D)

 

[Gareth elliott]

Looks like a gall crab, my experience was it irritated my Pavona and it started losing tissue but usually they die and are covered over as the coral grows. If its mated female they can reproduce.

 

[DSC reef]

Hard to tell for me, possibly mesenterial filaments

 

[tupes]

That looks like the mouth of the hammer. Does not look like a gal crab because it looks like tissue not a crab. I had a gallon crab in a brain coral once. That thing looks like the devil.

 

[NanoDJS]

+1 DSC

 

[Jé123]

Hard to tell for me, possibly mesenterial filaments

Here's a picture of the coral getting asleep and it looks bigger, are those filaments a good thing or a bad thing? Should I do something about this?