Treat that more as a rounded figure since data is less precise on fish. Anything that’s not at that density would a rounding error at most. The densities of farmed fish are truly insane - usually far above the already high densities you see for land animals. The high level of concentration is not only terrible for the fish themselves, but also leads to huge pollution. Putting an unnaturally high count of fish in one area heavily concentrates their output

Parasite and disease rates are also super high. High usage of antibiotics in fish farming also lead to stuff like antibiotic resistance

I could keep going, but instead I’ll just show some photos of the absurd densities: