Skuza, I'm no pro on this, but I'm trying to retrieve my Lunker status so here are my thoughts.

Normally HSB would not be considered an ideal predator for bream/sunfish because they normally inhabit different spectrums of your pond. (There's a $3 word to describe these disparite tendencies but I'm too lazy to go back and look) Which is to say HSB like to cruise around open deep water and attack their prey. That's is why you can find HSB and SB busting shad early and late in the day out in the middle of a lake. Bream/sunfish tend to inhabit much more shallow and structure related areas of your pond, areas not normally associated with HSB hangouts.

The interesting thing about your situation is the clarity and depth of your pond. Seems like you might have a greater probability of HSB predation of bream in your situation than in a more turbid and shallow enviroment.

Those are my thoughts, the pros will better answer your question.