I was reading an interesting article here: http://www.reefsmagazine.com/forum/reefs-magazine/100587-great-temperature-debate-part-iv.html Of specific interest was a suggestion for the summer months: Run your temp most of the time at the usual temp, but once a week, spike it up to 84 deg for a couple of hours. The theory is that it causes the corals to acclimate a bit to higher temperatures, without really stressing them so badly. That way, if there is a chiller failure or really hot spell, they can handle the heat better, and have a much higher chance of survival. Basically, you stress them a bit, but possibly save there lives if things go wrong. Interesting idea. A couple of obvious issues though: 1) If your tank water/light/etc are no so perfect, that extra stress could kill. 2) Bumping temp up to 84 for a few hours, then quickly back down, once a week, is not all that simple. 3) That "temp spike" is probably as likely to go wrong as any other problem. So are you really reducing risk, or replacing one risk with another. Thoughts?