My point is they are a predator that will eat larger fish than most people would think they would. Not just a bottom feeding fish that eat grub and worms on the bottom of a pond.
BHs feed from the bottom all the way to the top. They eat everything BG eat and can also eat mid-size forage fish. Other than things like carp, buffalo, and tilapia that can solely depend on a vegetarian diet, I know of no other fish that can attain the biomass of BH in a fertile farm pond without additional feed. Perhaps BG, but they would likely die from a DO event shortly after achieving a biomass of 800 lbs/acre in an un-aerated pond.
I would not put them in any body of water, but I do know they will be hard to catch when you have a large bass population. The main question would be, do they eat too many smaller fish that the bass need or do they make good bass food them selves.
To willfully stock BH in pond would require a desire to have them. Even though I have fond memories of fishing for BH in my grandfather's pond and eating them for supper and breakfast, I probably wouldn't stock them in my pond either. Personally, I don't think there is anything wrong with feeding them in an impaired condition. In your case where you already have them, I would target them occasionally, enjoy catching them, and when caught one, I would clip the spines, trim the tail, and return the fish to its fate (though I wouldn't be averse to eating it). Whether it feeds a bass will depend on the size of your bass, the size of the BH, and the presence of other large predators that might compete for it. Worst case ... it recycles by other means.
As to the main question, there is most frequently both winners and losers in an interaction. The only fish that might benefit from a 13" BH gorging on BG would be a much larger predator fish like a 22"+ LMB that can't make efficient use of the prey that the BH was eating. The losers would be 12" to 16" LMB which would target the same fish the BH is capable of eating.
