Over the years my dad and I have tried to keep Sturgeon in our Koi pond. We have not had much luck. Weve purchased them somewhat small 3-4 inches and not sure where they end up. I have a feeling someone in the pond may be an undercover carnivore. OR the Sturgeon are starving to death. Sturgeons have downward pointing mouths, and Im not sure if our hungry Koi let anything stay settled on the pond bottom. Anyone have any luck with keeping Sturgeon in a koi pond. Not sure how many gallons the pond is, but its approx 15 ft x 8ftx 4 ft deep.