Depending on the Spring water temp, you might be able to have trout all year long if the water temp in the upper pond is below 70°F all year long. Cecil keeps trout alive all year long with 50 gpm into 1/2 ac pond, but the ground water temp here is 53°F.

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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).