Welcome to the forum. Be prepared to think about using a liner for the pond, or a sealing product to mix with the soil in the part of the pond that is below the water line after you have removed all the rocks - think of a screener if there are a lot of rocks. Not too sure yet on the sealing product on sand, I am running a test this Spring on using Soilfloc on sand.

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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).