I'll restate from my last reply on your other thread that there technically is no cure because we do not know the cause. Some speculate nutrition (obvious) along with stray voltage, lighting, water quality, territorial disputes, etc. Regardless, their bodies are not getting enough of something and stressing. An interesting note, at work we have very few hlle problems, but the tangs with hlle are the ones on the lowest end of the totem pole. In other words, those that are picked upon most are the ones with hlle, semi-picked on have a little erosion here and there, while the dominant has none. This occurs in two different displays with two different species of tangs. An Atlantic blue tang with horrible hlle and being picked on heavily (not anywhere near dominant) was removed into a holding tank by itself and was clear of hlle and any other lesions within 2wks-30days time. There is no live rock in either the two displays or holding tank. What does this mean? You tell me lol. Personally I think it has to do with nutrition and community stress. Keep up the water quality and feed a variety of foods. It wouldn't hurt to use an additive like Selco. Sorry if this doesn't help...