When I first put HSB in my 4.5 acre pond, I was not really that excited about it. My fish guy kept touting them and convinced me. I was more along the lines of only having 'naturally existing/occuring' fish in my pond. So, I started low with only (5) HSB. I didn't see them for a year. When I did finally see them, it was because an area of water about 15' square was just boiling with bait fish. When we went up to the area in a boat, these 5 HSB were corralling and eating golden shiners.

I've been sold on HSB ever since.

For a 10 acre pond, I'd go with 10-20 if you just want to try them a bit. At certain times of the year, you can buy 9"+ HSB thus reducing the chance of predation by LMB or other predator fish.

They hit feed aggressively, and that's a good way to be able to see/locate them in your large pond.

Excerpt from Robert Crais' "The Monkey's Raincoat:"
"She took another microscopic bite of her sandwich, then pushed it away. Maybe she absorbed nutrients from her surroundings."