In the ocean, fish measuring five to six meters long are not uncommon. Because the ocean is vast enough, it has an abundance of food to sustain the creatures within it, allowing them to grow freely.
However, land or lakes are not quite the same, as they often face various limitations, which means the fish in lakes rarely grow very large. The Black Lake, however, is different, because the Black Lake belongs to the wizarding world, and the wizarding world possesses things like magical creatures.
More importantly, over the years Ye Feng has frequently "fed" the fish in the lake (baiting fishing spots), resulting in the fish in the Black Lake being relatively large. Therefore, it was entirely reasonable for a fish capable of swallowing Ye Feng in a single gulp to appear in the lake.
Chapter 283