If using the agricultural lime (I'm assuming grey) it isn't as strong as the white lime (I'm assuming it's hydrated lime). I'd keep testing the pH of the pond and use the cheapest lime.

You can kill the fish in the pond if too much hydrated lime is added. Much harder to do when using agricultural lime.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).