Luciocephalus pulcher - SE Asian fish that I believe only gets 8" or so. A 12" specimen would be simply stunning (and dubious). Their native habitat is swamps that can be considered blackwater, with low pH and low hardness. The probable reasons for their quick demise are stress, low resistance to common bacterial diseases, and improper husbandry. They really thrive when you can you provide them stable low pH and lots of live food - preferably danios, worms, cyprinids - not live-bearers, as they can introduce a host of serious bacterial contaminants. I've seen a few take frozen foods, but most pass on it. Good luck, they are very interesting!
J