Hammer coral heads falling

[Chirag96]

The heads of one of my hammer is falling off. As you can see in the picture. I am not sure the reason but the other hammers right next to it seem fine.
Can someone tell me what the issue is and what can be done to rectify it?
My duncancs had a similar issue 2 weeks ago their heads started falling off and dying one after another.
My water levels are:
Alkalinity - 8.4
Calcium - 480
Nitrate - 3
Magnesium - 1450
Phosphate- 0.04-0.1

 

[Mr. Mojo Rising]

its called bailout, the coral is unhappy and releasing itself to try to find a new home. You have to find out what is bothering the coral so much. The picture is too blue and hard to see. but seems you have corals very close together, maybe some coral warfare going on? IDK. A pic in white light will help, how old is your system?

 

[Chirag96]

My tank is 1 year old. But the other hammers near it seem fine.