I have one fish for sure that I still cannot decide whether it is a P. albicans or Brachyplatystoma vaillantii, as you suggest. (((here is the ID thread on him http://www.planetcatfish.com/forum/viewtopic.php?f=13&t=30240&hilit=+vaillantii ))) The same experts could not be 100% sure either in my case. They grow to immensely different sizes - vaillantii is a monster at 4.5' max. So, time will tell. Mine has been in a pond for a year temporarily. I never see it except fleeting shadows/glimpses but soon, hopefully, he will move into a large tank and then I'll try to ID him again.