HELP!!! My brain is dying

[tthemadd1]

My old brain is dying off. Tried iodine dip last night looking worse today. Haven't fed it in a month or so. All was good then in 24 hours it's looking bad. Anyone have any advise? Going to test water in a few minutes.
Ammonia 0
Nitrite 0
Nitrate 0
Calc 450
Alk 7 a little low
Salinity 1.023
Phos .25. Has been for a year
Temp 78

 

[btldreef]

It could be the alkalinity.

 

[tthemadd1]

What I don't get is it has been low for months and months. The montiporas are doing fine as is all the other corals. I guess it may have been stressed for the past year but all of sudden it couldn't take any more?