Thanks for all the replies. My ca is 450, and dkh is 7.I know 7 is a little low, but never seems to afect health, just a little growth. Has been this way ever since the tank has been set up. All my caps,digi,milli seem great still along with all lps and softy's, but light has not come on yet. Was only 3 people over, 2 friends and one of their kids. I did not see anyone touch anything as they were just getting some frags. We have 6 or 7 other reef tanks, and a few othermisc tanks and no issues. First thing I thought was sabotage, but I really can not see that from them. The garf was about the size of a softball, and all the skin turned to muck, and all that is left is death. Fragged as much as i could after I notice 3/4 death, but all frags died as well. I have had garfs long before go great, then bad, then great, but never a over night death.
All I know is when I came home from work, I took a look and my jaw dropped in shock. I seen a bright with coral and was like oooo no. I was showing it off to anyone that came over on how sexy this garf was, guess it turned on me.