In need of help... URGENT !!!!!!!!!!!

[Julie]

I'm going to chime in on the temperature; I've been keeping mine at about 73-74 for 2 years now; it really swings in the summer with the heat.  This is when the hair algae kicks in, not sure if its the temp, the sunlight, or perhaps my lack of attention during the warm months.   

Regarding the ammonia, is it .2 ppm....minimal but it should be zero.  There is something causing ammonia which is the beginning of the cycle.
Perhaps bacterial die off in the live rock or as mentioned coral die off  from the temp change.