FWIW-I can't help on the amounts Bullhead but I did exactly the same exercise you are doing now, last year. For my 1/4' pond it was hundreds of pounds of hydr lime and I had no way to ensure I got the PH high enough for long enough. Too much work and guessing for me. Instead I got my RUP license online and bought 1 gallon of Rotenone, drew my pond down, and killed every thing with fins.