Now they are all slaughtered live fish, or bought and slaughtered in the freezer.

The following is Baidu Encyclopedia's information about the dish "smelly fish".

It is said that more than 200 years ago, fishermen along the Yangtze River transported mandarin fish, a valuable aquatic product from the Yangtze River, to Huizhou mountainous area for sale in wooden barrels every winter (then called "barrel fish"). On the way, in order to prevent the fresh fish from deteriorating, a layer of light salt water was sprinkled on the first layer of fish, which was often turned up and down. After seven or eight days in Tunxi and other places, the gills were still red, the scales did not peel off, and the quality did not change, but the epidermis exuded a special smell that seemed stinky but not smelly. However, after washing, it is slightly fried in hot oil and cooked with low fire, which is not only odorless, but also very delicious, and has become a well-known delicacy with a long reputation. Nowadays, barreled fish is no longer used to cook this dish. Instead, it is fresh peach-blossom mandarin fish produced in Huizhou (peach blossoms bloom every year and grow fattest when spring news comes out), which is pickled with salt or thick fresh meat juice and cooked by traditional cooking methods, so it is also called "pickled fresh mandarin fish".