Translation: Grab the rod and go if you got a dead fish.
This is a superstition that Chinese anglers believe in. The informant is an angler, and he learned this saying on the Chinese online forum of fishers. The dead fish is believed to be attached to the fishing rod by the water monsters(水鬼). If the angler keeps fishing, he will be the next water monster. To protect oneself, the angler must burn the paper money and prepare meat for the water monster, a ritual to appease the water monster. Although the informant does not believe in monsters, he still respects and shares this term with others. The informant is also sure that all anglers in China know this term as it’s a general term.
As a well-known term, the saying has some practical meaning, while the ritual is a common way Chinese people deal with creatures that are not human beings. The saying itself, which warns anglers about dead fish, might be a cautionary saying. When one catches a dead fish, it might mean the water is contaminated, which causes the death of the fish. Thus one should stop fishing at that location and avoid eating the fish. The ritual of appeasing the water monster involves the Chinese superstition of offering food and money to things in another world. Burning paper money is a way to provide money to the dead, and it is believed that supernatural creatures can consume the food humans provide them. By “worshiping” the water monster, anglers can avoid being harmed by the water monsters.