It is best to somewhat spread ag lime out over the pond bottom. It will still work if you only spread it out in a few places but not as well or efficiently. Keep in mind you are treating the cause of the low alkalinity (the dirt) as well as the effect on the water.

IMO in most cases spreading the lime out in an upstream inlet or the dry watershed is not a wise use unless there are no other options.
A spreader truck backed up in several locations around the pond is the best way absent a boat/barge application. When I get the spreader truck to come I have them dump a small % on shore for me to put out in the pond by boat.

Bill's test idea is a good one. To best replicate the effect on the pond put about 1 inch of pond dirt compacted on the 5 gal bucket bottom and allow the turbidity to settle. Then add the lime and test.

Last edited by ewest; 05/10/17 12:18 PM.