Hammerhead Branch Issue?

[jorjef]

If you are talking about the thin milky membrane that goes down the branch it's not uncommon to have it recede a bit. To come off to the point of exposing the skeleton will not be good in the long run. Keep water conditions right and it might grow back enough to cover the skeleton. If you see brown jelly forming around the opening throw it out or if you want try to treat it or cut off the sick head. All crabs are deviant pains in the ass my advise get a hammer and let him have it.