George :

I believe with active management you can be successful with what you are planning with your small pond. The trick will be to keep all the factors in balance. Here are the questions I see. One -- will there be enough zoo/planktonic , FA and natural food for the pery species BG/RE/tilapia. Two -- will the water quality support their number and growth along with the HSB. Three -- Assuming 1 & 2 can be done can the HSB control/balance the pery enough to keep them from over populating to the point of first stunting and second reaching to high a biomass with the resultant loss of water quality. In a pond that small (assuming there is not a bunch of brush/trees in there) the HSB will follow the food ( they may be able to see or sense them from the other side of the pond) and will only be limited by gape size (size of mouth opening). ewest