Bleached?

[sac10918]

Hi,
I have had an acropora coral in my tank for about 2 months. I was just thinking the other day how good it was looking, and today I notice that it is completely bleached.
I have 1x70w 14,000K PowerPaq HQI lights on a 24 gallon tank which are on for 12 hours a day. I have no actinics or any other lights as this is an aquapod.
Could too much light be bleaching my corals?

 

[fishieness]

it definatly isnt too mught light. you probably dont have enough unless it is RIGHT at the top.
however, there are a huge number of problems why it oculd be bleaching. But seeing how it happened in the course of a day, RTN is most likely, which, once again, has a large number of causes. first off, what are your levels? esspecialy phosphates. have you added anything recently? what? do you see any red bugs or flat worms aroudn it. make sure to look SUPER carefully. ANYTHING that isnt coral flesh could be one because they are tiny and most are very well camoflauged.
how much flow does it have? where is it in your tank in relation to the MH? what fish and inverts do you have? how old is your tank?? what have you added most recently?