Pachyseris is one of my long-time favorites. Eric Borneman once called it the No-Polyp Stoney coral and it's an apt description. Bright light and strong current (sediment settling on it is the biggest thing to avoid, as it doesn't take much for long before you'll start to get tissue recession underneath the sediment, and once that happens it's easy for boring algae to get a foothold on the skeleton and cause further recession). It'll lose battles with pretty much every other coral out there if they end up in close proximity, so avoid that as well.