For my pond, it's solely the amount of light. When there was a big maple tree there shading the pond, they'd eat in the shade in the daytime. Now that it's gone there will be some feeding response during the day, but very minimal. Dawn/dusk is best.

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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).