What's wrong with my hammer

[evolved]

I'm sorry, but it looks to be a lost cause now. It looks like brown jelly disease (BJD); a bacterial infection. Once it sets in on Euphyllia like this it's tough to stop.

 

[fishmaster818]

Non of my other corals are like that there all growing and look great

 

[eliramos]

It looks to be shedding the yellow branch is this bad or is it fixing its self

Oh man
I didn't see this picture before
The dip has instructions on the bottle
You place the coral in a Container with a small powerhead or just something to keep the water circulating(use water from existing tank)
Then you admit the drops according to the amount of water you used
I let my corals sit for about ten minutes.
After that get some new salt water and dip the coral in that clean it off a bit and place it back in the display.

However yours is pretty far gone I feel like medicating it may just stress it out too much.
Sorry man you can try the dip but either way you may have lost him.
Good luck bud!

 

[fishmaster818]

Why did it happen

 

[Lidofishieboi]

Sorry bud, but that's a goner.

 

[evolved]

Why did it happen

It's impossible to put a finger on the explicit cause. However, Euphyllia are one of the more susceptible corals to BJD, especially if the tissue gets torn.

Here's a good general read on the topic: Corals - Bacterial

 

[Ladysaber]

Get your dkh up. It's on the low end. Nitrate should be lower as well. Try and do a water change and retest your params. Your tank will be happier if you do.

 

[427HISS]

Have you made any changes in your system ?

Lighting ?
Water chemicals
Big water change
PH swings
Water flow
Stinging by other corals
Etc....?