If you don't have plants that suck up a lot of water (those plants like to live in moist to wet conditions, i.e. have their "feet" wet), then I wouldn't worry about the plants using too much water from the pond.

For instance, the figure around here is that a grass lawn needs 1" of water per week, but it can get by with less.

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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).