My pond was built almost four yrs ago and is a little over 3 acres. Cnbg stocked twice, once in Nov and again the following Feb. The first lmb were stocked as fingerlings the first of that June.
I had the pond e shocked at the first anniversary of the lmb stocking and again the following year. So I knew our cnbg numbers were high based on what I stocked and what the survey showed. Jludwig, made a good suggestion when he recommended an e shock, otherwise you are pretty much guessing and here, Overtons Fishery will run some water test at the time they are there to run the shock boat.