Float them out. Tie something onto it so it'll float, but you can cut the floats off and let it sink. For instance an upside down 5 gallon bucket will give you around 40# of lift (filled with air of course).

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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).