A great big thanks to all. I have my answers, and a direction. All I did was pose a question or two, it was the answers that made this great.

Rex, If I was running close to max. standing crop, then I would be more concerned about adding Tilapia to the pond than the trout. I think there would be more of a potential oxygem problem during the heat of the summer than winter if the aeration system were to go down. I was trying to figure out what 80% of the standing crop potential was, to make sure I had room for the Tilapia in the summer, and the trout in the winter.

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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).