You need enough to raise PH to 11-12. Fill 50G tank with pond water you will be treating, measure increments of lime added to tank until PH level reached. Extrapolate data to figure amount needed to treat the pond fully. Drain pond to lowest level possible with trash pump and estimate gallons remaining.

1 acre = 43560 sq ft
1 acre inch = 27,154 gallons
1 acre foot = 325,853 gallons

For example:

Suppose it requires 1 ounce hydrated lime to achieve PH level of 11-12 in 50 gallons of your test pond water.

Let's estimate 1 acre foot of water [325k gallons] remains after pumping - divide 325,853 by 50 = 6,517 ounces.

It would require approximately 407 lbs of hydrated lime to achieve PH level of 11 in pond required for fish kill.

50 lb bags of hydrated lime cost $9. 407/50 = 9 bags.

$81 cost of materials - but you'll also need a ph strip test kit for a few bucks to make sure your pond ph is at the desired PH level. I'd buy a few extra bags to be safe.

You probably could have figured all this out, but I had some fun doing it and might do so myself in a pond this Fall so I needed the practice.

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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