Brown Coating underside of Hammer

[AaronFReef]

I have a hammer that I’ve had for two months and it has been growing well and sprouting new heads until about a week ago when I started dosing hydrogen peroxide for some dinoflagellates/cyano I’m battling.

It has been retracted and faded for about five days now and yesterday I saw this on the underside:

I dipped it in 10 drops/ounce of lugols yesterday and today it looks like this:

The brown coating is thin and has some areas it looks like wiped away to reveal normal tissue under it. The tentacles that have the brown on them seem extra droopy.

What is this? I did some reading and have an idea hence the lugols but want to let the community lead the thinking.

 

[Tennyson]

What are your current parameters?

IME euphyllia can be very sensitive to changing parameters, so my first bet would be the hydrogen peroxide is not agreeing with it.
This is a wild guess, but could the browning tentacles be a symptom of bleaching? As the coral expels and loses its zooxanthellae elsewhere, perhaps the drooping areas are more shaded and aren't bleaching as rapidly. The drooping tentacles may be the corals attempt to shade itself from getting bleached more.

 

[AaronFReef]

Parameters:
Alk 9.1 dkH
Calc 480 ppm
Mag 1320 ppm
PO4 0.02 ppm
NO3 1.0 ppm
pH 8.1-8.3
Temp 78
Salinity 35 ppt

Doser and daily monitoring of most Params while I fight the Dinos.

Good catch. Forgot to mention those.

PAR at that coral is about 125-175

 

[AaronFReef]

Also I realize the pic didn’t show this well, but it has spread about 5x in 24 hours.

 

[AaronFReef]

What are your current parameters?

IME euphyllia can be very sensitive to changing parameters, so my first bet would be the hydrogen peroxide is not agreeing with it.
This is a wild guess, but could the browning tentacles be a symptom of bleaching? As the coral expels and loses its zooxanthellae elsewhere, perhaps the drooping areas are more shaded and aren't bleaching as rapidly. The drooping tentacles may be the corals attempt to shade itself from getting bleached more.

I thought bleaching turned them clearish/white and dense zooxanthellae made them more brown. It’s definitely in the shaded areas. It seems somewhat deflated around the mouth as well.

 

[AaronFReef]

So I’m thinking brown jelly disease. Can anyone confirm? Do I need to take a ziplock bag and dip it into the tank and place the coral in it and chuck it before it wipes out my tank?

At this point in two months I’ve had monti eating nudis (which I aggressively culled infected montis for and may have defeated), a Dino outbreak, flukes on my QT tank. Man this hobby can suck sometimes.

 

[AaronFReef]

I didn’t see it extended this morning but it seemed better a bit. It’s usually deflated at night and in the morning but it was less so this morning than it has been. I did some reading on brown jelly disease and it didn’t sound too similar. Doesn’t get worse in the dark, doesn’t cost the top.

I have a microscope if that would help identify it though I imagine I’d have a hard time grabbing a sample from the underside of an extended tentacle before it retracts fully.

 

[AaronFReef]

It has definitely spread today. Anyone able to help me...?