It will be interesting to see what you find out. Feed degrades over time, vitamins lose potency, etc. Normal shelf life is 12 months, but I've fed feed that was 2-3 years old. The fish didn't seem to know the difference, but since I am not a production facility, I don't typically keep tabs on FCR, etc.

A supplier that raises trout said they had to switch suppliers 2 years ago. Same feed supplier, supposedly same food but their FCR's dropped roughly 15% and the price of the food actually went up $1/bag. It was a big enough change that they had to cancel a few fish contracts.

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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).