Funny you should mention that, as I love the look of sturgeon in the aquarium, they give you the closet look to a shark in a fresh water aquarium, (in my opinion). I had one about three weeks ago at 7 inches that ate well and was always on the move. He was in a holding tank with a 5in GATF, 5in silver arrowana, 6in clownknife, 6in arapima, three 4in indo dats, and a 6in dorado and I don't knwo what in God's named happen to him. Came home to feed and noticed it was just not there. All the fish ivolved was his size or smaller and no one had the enlarged belly look. I could not find any traces of him anywhere, unbelieavble. To this day I am in AWE that I don't know what happen to the damn fish. I really liked the little fellow he he was so active and I rasied it from 3in. Now I want another one!