It might. Just bounce the water overflow over some rocks or other material to get it mixed with the air. It'll help it outgass any nasties, and oxygenate it on it's way to the pond. The only downside to that is that it might be warmer than the pond water.

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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).