Are you absolutely positive that they are YP? It's not only water temp that influences their spawn, it's also photoperiod. I haven't heard of YP ever having a rolling spawn like BG.


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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).