I have not either. But estimates vary widely.
I have found myself mis-estimating my fish' sizes so often that now I choose to include a scale for my own sanity. [see picture attached of my female Metynnis maculatus (3 views), which looks rather similar to the specimen in the photo posted above. The second pic shows both male and female + scale]
With "...about 8 inches", but no direct point of reference, we have no idea of the actual size of the fish. Interestingly the parrot cichlid next to it suggests that it may be
View attachment 1386377 less than the stated 8 inches.
Regardless, a pacu cannot have that adipose fin.
But it is all cool among friends.
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