Why are ricordias melting? There are similar questions in this forum, but so far no definitive answers. In my case I've had 5 ricordias (individual and colonies) growing for over a year. They really looked good. Encouraged by this I ordered 6 new ones from the same on line source with over night shipping. On arrival they all appeared a little shrunken, as expected. After acclimation they were placed in the tank and looked OK (for new arrivals) for a few days (longer than the guarantee) but then began to shrink and melt. Of the 6 new ones only 2 now remain, and they look fine. However, 2 of my long established colonies completely melted and disappered almost over night at the same time as the new ones. The remaining 3 established colonies look unchanged. I don't get it, do you?