SPS Tank O Death

[Jason McK]

C,
I have seen the slime coat lose in my own tank. It has occurred with High SG and again with a fist spike of ALK. Basically the coral starts to look dull and there is no polyp extension. I believe it is a recoverable situation as 4 or 5 of my corals have recovered. But others did not. The next stage tends to be tissue lose and growth of algae on the skeleton.
Unlike RTN or even STN the lack of a slime coat (IMO) indicates a slow progression of a stressed coral with 2 outcomes a return to health or death.
I don't think this helps too much with the diagnosis of what is causing it but instead leave us right where we are.
What can be stressing your corals.
We have ruled out measurable water parameters
We have ruled out chemical or other coral attack (usually kills small sections of coral)
We haven't ruled out silicone leaching
We haven't ruled out unmeasurable water parameters (contamination) but you would think it would effect everything

Light sure is a possibility. your running a 150W DE right? what is the UV is not being stopped? That would do it

J