Don't forget that EVERYTHING in the pond eats YOY fish. From Dragonfly nymphs to adult RES. You could see recruitment as low as 1% after year 2.

http://www.tandfonline.com/doi/abs/10.1577/1548-8659(1946)76%5B190%3AROSAGO%5D2.0.CO%3B2#preview

I believe that those test ponds were only stocked with BG fry, and they tried to only have BG fry in them. Now throw predators in the mix and think about what the survival rate would be.....

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).