You did good so far, it could have been a lot worse. A siphon can move a lot more water than an overflow pipe like you have. You'll be suprised how much water it'll flow.

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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).