Look for an indoor/outdoor or pool thermometer. Check the water temp in the pond vs the barrels. If it's more than 4�F difference you'll have to acclimate the fish to the temp. If the temp differential is greater than that it's a pretty big shock to their system.

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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).