In my experience and opinion using hydrated or quick lime is risky as to how well it will kill fish. There are likely several if not numerous variables to consider to insure a fish kill. The main thing IMO is the starting alkalinity and total hardness which have big influences on the buffering capacity of the water body. I would never rely on hydrated lime to eradicate fish especially if tolerant fish are present. Some fish species are more tolerant of a high pH than other species. My go to fish eradication chemical is rotenone. It has never let me down for 100% success. If I was doing it without rotenone and a complete kill was important as the goal I would have reduced the existing 3/4ac of new water down to a even lower pool maybe only 1 ft deep or less. then added twice as much hydrated lime as suggested.

Last edited by Bill Cody; 05/04/21 08:59 PM.

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