I was at my LFS today and I saw the strangest looking fish. It's been there for a couple of weeks. It's listed as a "Blue Dolphin Shark." What is that? I've googled it and have come up empty handed. It has a tear-drop shaped body with beady little eyes and a mouth that looks like its always open (round mouth). It's blue/gray and about 3-4" long right now. The employee I asked said it uses sonar to find its way around a tank. It eats anything that will fit in its mouth and could double in size in a year. Any ideas?