Bill C, I think the key to Bob's comment is "optimal" growing days. I think he's meaning when the water temp is between "X" degrees and "X" degrees. Neither too hot nor too cold.

But like you, I have a hard time believing it.

"Trust but verify" and I haven't been able to verify it yet.

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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).