, Head and Lateral Line Erosion
I don't know why it strikes tangs and angels most often, that just seems to be the case. BTW, the name pretty much describes the problem, the lateral line begins to erode at the head above the eyes and continues it's way back along the lateral line. Because the lateral line is used to detect the earths electromagnetic field and helps keep the fish oriented in water, some believe stray voltage is a contributing factor in this syndrome. The truth is, no one really knows
what causes it.