You need something to measure fish length, weight to 0.1 lb and a log book to keep track of the fish.

Compare weights to the ones listed here in the archives:
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=160456#Post160456

www.hoosierpondpros.com

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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).