I'm no expert, but could you have some disease hanging out in your tank that is doing in these fish. Did you carefully examine these fish to check for disease?
The other thought is stray voltage. You're young and health.....stand barefoot and put your hand in the tank. Do you feel a tingle? You could do this more precisely using a VOM or multimeter. With it set on volts AC, put one probe end in your tank and the other to a good ground. I always use the screw on the front of a wall plug cover....that's a good ground.
Love the idea of having corals more than the fish as I can't frag the head off my fish to grow another hah
So I bought a yellow coris wrasse from ACC Saturday. Have yet to see him.