Hammer Coral...stressed, shedding?

[Meb3]

I've had a single head of hammer coral in my tank for about 6 weeks in the same location, (bottom third of the tank). It was fully extended during the day and about 4" in diameter for about 5 weeks. A week ago it started to shrink to about 1.5" in diameter and I noticed that there was a new head growing behind the first. The new head is smaller, but fully inflated. Today I noticed a ring of tissue hanging from the front of the first head, (see photo).
Everything else in the tank looks good including, softies, zoas, LPS and SPS.

Is this a normal fluctuation in behavior or signs of disease?
Is it stressful when new heads emerge?

My tank is a 45 gallon mixed reef with a 10 gallon sump, a skimmer, media reactor running GFO and carbon, a refugium and a power compact fixture with two 96 watt bulbs, (actinic and 10,000 K bulbs, one and three months old).
I have a pair of Ocelaris clowns, a Coral Beauty angel and an African Firefish.
Parameters are temp 80.4, ph 8.3, sal 1.026, dkh 9, calcium 420, magnesium 1315, nitrates and phosphates undetectable.

Nothing has changed in the tank except adding a few zoas and a nepthea tree coral, which are fine.

 

[Meb3]

Does anyone have any advice? Thank you.

 

[dz6t]

Looks like it got stung by other coral, can you please take a photo of the surrounding corals?

 

[jason401]

That coral beauty could be the culprit too

 

[dz6t]

Good call.

 

[Bobbofin]

Coral beauty are beautiful because they're fat on eating lots of coral and very healthy! Would not have any Centropyge angel in a tank with coral except a maybe a pigmy flameback or cherub. I just would not trust them.

 

[Meb3]

The attached image shows the surrounding corals. The closest are the Green Star Polyps about 4" away.
The Coral Beauty has never shown any interest in nipping corals (that I've seen). He forages for algae between meals.
I rechecked my parameters. The Calcium had dropped to 360 and the Magnesium to 1200. All others were the same. I do weekly 8 gallon water changes, but maybe I need to start dosing.

 

[stingythingy45]

That head looks like it is receding and in rough shape.
I would also blame the Coral Beauty.

 

[dz6t]

Give it several days to see if it opens up again. Looks like it still has all the flesh intact.

 

[Meb3]

So nothing close enough or aggressive enough to sting it?
Low Ca and Mg not enough to affect it?
Thanks

 

[Meb3]

If there is left over food settled on the hammer after target feeding, could the detrivores (bristle worms, hermit crabs, Nesarius snails) be bothering it?

 

[stingythingy45]

I have never seen or heard of detrivores bothering hammer.
Also,I would rarely target feed frogspawn or hammer.

 

[dilligaf29]

I had one do the same thing was fine until I added new frags and the placement of the new frags was causing to much flow to hit the hammer once I moved it was fine couple days later

 

[Meb3]

Is this brown jelly or just dead tissue?

 

[LoveTheReef]

Brown jelly. I'd turn off the pumps and toss the skeleton before it spreads...

You can try an iodine dip etc to try to save it but in my experience euphyllia are hard to bring back .. especially if they look like the picture .. :-(

Sent from my SCH-I535 using Tapatalk