stn from coral chemical warfare?

[jasony816]

I have some aptasia in the tank and its very close to a hydnophora, I would say 1-2" max distance. I notice that some of the aptasia is going away so im sure they are stinging each other. My questions now is ever since I notice this I am seeing STN in my SPS and some have totally just RTN. I run carbon/phos and the following are my parms:
temp:78-79
ph:8.1
nh3:0
no3:0
po4:0
cal:440
alk:7-8