Endurance is made by the people that were at Optimal. Years ago Optimal was called in to a company that was raising Yellow Perch indoors for the fresh fish market. They were selling filleted fish, not whole fish. IIRC by switching to Optimal the company reduced the fish fat that ended up in the waste pile by 20%-30% and increased the fish flesh by approximately that amount. .

So in my mind, if that happened to fish that were 1-2 years old, what would that mean to fish in a pond that would be living for 5-10+ years? I'd think that it would add to their life span by reducing fatty livers, etc.

In my personal pond, when I switched from Aquamax to Optimal when Optimal first hit the market I say a large reduction in the amount of FA in my pond.

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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).