Heres several of mine. The double head largest one died...after I added "Black Powder" to the tank. Thats the only thing I did different. The smaller ones were ok. The large "heads" had holes in the surface when polyps werent extended. Like some of the particles landed on the surface and ate threw like acid. It was 4 months of struggling to remove damaged tissue..then hope..then another struggle...it finally deteriorated beyond help. Anyone else have this happen with ANY type of coral??