I just got my first brachyplatystoma juruense and put him in my 55 gallon tank with a similar sized rtc. I don't know if they are compatible because my new juruense would stay at the top of the tank but when I put the juruense in my ten gallon tank he sits on the bottom and is doing great. I tried re-introducing him in the big tank but as soon as his whiskers touched the rtc's whiskers he was back at the top until I moved him back to the small tank. I guess my only option is to set up another 55 gallon tank and put the juruense in his own tank. Any ideas?