Strange Star Coral Ailment

[Cavalina]

Hi All, over the past week or so a portion of my star coral has started to die off. I'm not sure what is causing it, or what to do. Nothing else in the tank is impacted. Here's a picture below -- any suggestion(s) on what it could be or what I should do? (It's the white part at the bottom of the coral -- that all used to be "alive" last week). Thanks very much in advance!

 

[Cavalina]

Here's a better (non-blue) pic btw.....

 

[58e970b2-3f88-4897-87ba-5]

Unfortunately I can’t help, but here’s a bump.... and the next question someone will ask:

What are your parameters?

 

[Cavalina]

Good point, I should have included that. Fairly normal parameters with higher nitrates for my softies....

ph: 8.2
Alk: 9.5 dkh
Ammonia: 0
Nitrite: 0
Nitrate: .5
Salinity: 1.023
Temp: 77F

 

[58e970b2-3f88-4897-87ba-5]

That salinity looks a little low. How are you measuring?

Also how long have you been growing that patch?

 

[Cavalina]

1. Just a standard $15 plastic hydrometer. Very similar to this one.

2. It's a couple of years old. First time anything like this has happened though!

 

[saltybees]

Does the bottom of it get much light? Maybe the sympodiums ( I think that’s what’s all around it) shading it too much

 

[Cavalina]

To be honest, if anything it gets too much light. It's at the top of my live rock and closest to my Kessel. But it's been there for quite a while without issue. So I don;t think it's a light issue (?), but I could be mistaken.

It's weird, the "dead" portion of the coral appears to be creeping upward. It's almost like it's coral gangrene or something I'm half tempted to take the coral out of the tank and remove the dead parts--an amuputatino of sorts--and see if that resolves the issue before it gets much worse.

 

[saltybees]

Ya I dunno sorry I’ve never had a star coral so I have no real advice, my sympodium grows* like an absolute weed though I could see it overgrowing anything near it lol