I wouldn't say impossible. Difficult maybe. Unscrew a bung, fill it with enough water so you can get it under the pier. Orientate it so the open bung is at 6 o'clock. Run an airline to it and fill it up with air, displacing the water. Screw on bung and you're done.

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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).