I tried Herbtana, and it worked well enough. The fish that were really sick died, however the rest lived. I could see a daily improvement while using it. Fish started eating, the ich diminished, and after about 2 weeks everything was back to normal. Did a massive waterchange, fired up the skimmer, and everything was right on point. Also, the treatment did no harm to any corals or inverts whatsoever.
After going thru that experience, I now QT everything before I add to DT. It's terrible to watch that happen to your fish.