I've seen FHM spawning on the underside of American Pondweed too. Plus look in the cover/structure archives for ideas on putting in artifical spawning cover.

I'd go the artifical route because if you want to seine the pond, it can be easily removed to seine. Lilies and vegetation not so much........

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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).