Davis bleaching, others fine

[Sipec]

My one favia has been the star coral of the tank, he's the biggest one I've had and has always thrived
But today I noticed he's losing color and flesh, mouths were gaping, and the skeleton is showing.
I did a water change yesterday, and never noticed any problems, although I wasn't looking for them
The odd thing is is that my other two favias don't show similar symptoms, in fact most of the other corals don't look too different than normal, except my pocilopora's a little scraggly, and my mushrooms are flat
Gonna check my salinity in a moment, I have a feeling it might have dropped
So what should I do to try to help it? I'm afraid of losing it
Also sry about the title, spell check strikes again (the heck Davis doesn't even sound like favia)

 

[Sipec]

#reefsquad

 

[Crabs McJones]

Are there any corals near it that may be sending out sweeper tentacles?

 

[Sipec]

Are there any corals near it that may be sending out sweeper tentacles?

There are some near to it, but they're like a few inches away
I tested my salinity, it's a bit high, but it has been. I've been trying to get it down
It's at 27 rn

 

[Crabs McJones]

There are some near to it, but they're like a few inches away
I tested my salinity, it's a bit high, but it has been. I've been trying to get it down
It's at 27 rn

Any changes in flow or lighting? Any new additions (fish or inverts) that may be picking at it?

 

[Sipec]

Any changes in flow or lighting? Any new additions (fish or inverts) that may be picking at it?

Nope
Messed with the flow a bit, but I think I turned it back to normal right after I did

 

[Crabs McJones]

Any pictures of the coral?

 

[Sipec]

Bout to take some

 

[vetteguy53081]

Likely possibilities:

Spike in Alk
Salinity high and youre getting a false reading
Too much Calcium
If on the bottom, getting irritated by sand
High water temp
any inverts )snail/crab) hanging on the favia ?

 

[Billldg]

Can you remove the coral? If so you could try dipping it in some Iodine based dip to help with any infection and stress.

 

[Sipec]

Now that I've looked at it, I don't think I turned my flow back down
Should i turn it down?
Could be alk
Salinity reading should be right, I test using a refractometer and calibrate it ever use
No sand, is on rock
My Arabic cowrie could've irritated it,.do you think he could've nibbled it? He's grazed zoas before, but haven't had any issues this far with hard corals
I can remove the rock the corals on, not sure dipping the entire rock would be a good idea tho

 

[Sipec]

Here's the other pic, didn't post some reason

 

[Sipec]

A few water changes and feedings later and I think it's getting better