In the public lake near here and private ponds near here both utilize the same area. Both spawn on sand bottom and both spawn on pea gravel areas. Muck? I haven't seen them spawning on that substrate unless they can fan it away to get to sand/gravel.

Anything you can do to get the proper substrate will increase spawning.

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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).