Your tank will hate you! If you're around when it happens there will be blue sparks coming out of the heater. We didn't see sparks with ours but the heater actually blew up. The ceramic piece blew away from the actual electrical portion of it. Once that happened there was a stray electrical current in the tank...reminds me that I still need to install the GFCI outlet...my gf reached in and got zapped...so unplug before you reach in. The water will look cloudy kinda milkish. All the coral will be mostly white some might have color but most will be completely sucked up and white. My zoos even turned white. All the coral will have mucus on them and over all just a horrible site. Most of my corals are recovering very well. I've got some spots that are bleaching but the other parts of the corals are regaining their colors.