I think you're right. These are either Spotted Gar (Lepisosteus oculatus) or Florida Gar (Lepisosteus platyrhincus). The two species are extremely similar looking and I can't tell them apart. They can be separated by geography because their ranges don't overlap, and sometimes by size because the Florida Gar is a little smaller, but in captivity those don't help. Spotted is the more common and widespread of the two.
