@snowleopard were there actually sturgeon there or was it only signed as such? This is in the same month as my last visit, which I noticed that the pond was empty (Though signage for sturgeons do present).
Like @Fargusno said, it last reported to house the aquarium's long-time alligator snapping turtle, though possibly temporarily. Still, what a wonderfully designed/planted exhibit!
@Rizz Carlton I saw signs of sturgeon but zero actual sturgeon. The aquarium was a bit of a disappointment, with a sign posted that mentioned ongoing construction and probably 5 empty tanks. Lots of water, but little in the way of fish. Also, the two big walk-through areas were almost devoid of any sign of life.