Brain coral in possible trouble

[coldhybrid]

I just switched over to full spectrum leds from 150w halide on my 30gal cube. I came home to my brain coral expelling brown stringy stuff from one of the mouths. Is this a sign that the its too much light or not enough or what everything else looks fine. LED's are at 20% on white and multi color channels and 30% on blue should i up it or lower them they are about 12in off the water surface. params are normal
SG 1.025
Temp 79
PH 8.3
DKH 11
Amm 0
Trate 0
Trite 0
Phos. 0
Mag 1250
Calcium 500

 

[Genesis Corals]

If the only thing that has changed is the lighting, then most likely it is getting too much light. Corals react far quicker to an increase in light then a decrease. Try shading it and see what happens. I have put a tupperware on my mesh screen to block the lighting on new additions and slowly moved the tupperware away, allowing all the light to hit the coral.