need help with coral

[leshampton]

I had this green acro in my tank for probably about year now. I noticed a few white spots. Well, I thought it was because I had just moved my powerheads around so I directed some more flow back to that area. The white spots didn't spread and I didn't really notice them anymore. Well, when I got home from work yesterday, the whole thing was dead! I wasn't the night before, not even close. I have been inspecting everything in my tank, as best I can, after the first time I noticed the spots. I hadn't seen any on any other coral. This afternoon when I came home, I noticed a branch of my birdnest had turned white. I cut it off, that was the only think I could think to do. I don't know what's wrong, I've never had this happen before. Here are the pictures.

 

[Toddrtrex]

First thing would be to test the water and report the current water parameters.

Beside the powerhead move, any other changes ?

 

[leshampton]

Water's fine. Everythings at 0. Calcium was a little low but I wouldn't think it'd do that. No other changes. I've been getting ready for an upgrade so I've not changed much on this tank in a while. The only reason for the powerhead move was because I took them out and cleaned them.

 

[Toddrtrex]

What is the calcium level, along with the Alk, and Mag. How about the salinity and temp ?

Just trying to trouble shoot here, and the more info ( with numbers ) the better.

 

[leshampton]

Calcium was at 350, Alk 8.0 dKH, Mag 1410. Salinity is at 1.023 and temp stays between about 79-81.

 

[leshampton]

Anyone??

 

[kar93]

The salinity is a little low, You should shoot for 1.025-1.026

 

[leshampton]

I know, but it's been like that for many months, so I really don't think that's it.