If you do put it underground, make a provision for a sump pump, or a drain hole in case something springs a leak. If you do put it underground, also have something that will shut off the power if the water reaches the pressure switch. Electricity and being underwater with an open connection don't mix.

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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).