Tangjiawan is a land of fish and rice, especially the fishery production and oyster breeding are developed. Because it is located at the mouth of the Pearl River, the tidal current is gentle, the seawater is salty, the temperature is moderate, the water quality is fertile, and plankton is easy to breed, so it is a good place to raise oysters. Oysters have been cultured in Yinkeng for over 70 years. The first person who came here to fight and raise oysters was the yamen in Xinhui County. At that time, they docked in Tangjiawan and found that there were many natural oyster touches on the rocks here, which were everywhere. The oyster meat taken out of the shell is fat and crisp, tender and delicious. They thought it was a way to make money, so they jointly invested and set up a "He 'an Oyster Pool" near Shi Die. They took out six or seven thousand taels of silver to hire people to cut stones, and threw large stones into the sea like land reclamation to build a "house" for oysters. The total area of oyster farm is 500-600 mu. At the same time, a 40-to 50-foot-wide oyster sauce processing factory and distribution office were set up, and six or seven vermilion posters with the words "more oysters" and "more oysters at one price" were obliquely posted in front of the door, and the business was booming. By the end of 19 and the beginning of the 20th century, gentry in Tangjia, Shanchang and Jida coastal villages and businessmen from Taishan, Baoan and Macao also took a fancy to the seafood resources in this area, and occupied the seaport one after another, opening more than 20 oyster farms, including Zhenyuantang, Breeding Pond, Xiangyitang, Sihetang and Yongshuntang, all over Zhuhai. Therefore, there has been a popular saying among the people: "Xiangshan is a good place in the world, and stones sell meat", which reflects Zhuhai's past.

However, the best geographical location for raising oysters should be the bay around Shi Die. The reason is that Tangjiawan is blocked by the Pearl River flood at the back ring mouth, the water quality in the sea area is stable, and the site faces the northeast, which is a natural situation. Every autumn, a large number of fish from the Pacific Ocean swim into the waters with suitable water temperature along the Pearl River to breed, which increases the water quality and fertility. The so-called "fish oysters are fat, fish oysters are thin." Fish shit is the rich nutrition of oysters, which will make you fat. The villagers call it "Li Genshui". The boss often measures the fatness of oysters through the fish products listed in the market, especially when he observes that the fat Li Sanyu (that is, the shad) has been sold for more than ten days, he will immediately mark a piece of red paper and invite the security guards and oyster workers in nearby villages to collect oysters in the sea. On average, oysters can be opened every day 150 tons, oysters can be beaten during the day, oysters can be cooked at night, and oysters can be dried the next morning. By noon 12, fresh oysters that have been dried to a semi-wet state will be packaged and exported. At that time, Hong Kong "Daxin" and other fishing companies sent two boats to buy fresh oysters and oyster sauce in turn every day. The processed oyster sauce was packed in 50 kg each, and all of them were boiled with 100 kg of fresh oysters for 4-5 kg of refined oyster sauce. Due to the good processing quality, the cooked oyster sauce has large colloid and less precipitation. It is like a bead dripping with chopsticks, smooth and golden in color, fresh and sweet in taste, like a kind of nectar. Those Hong Kong businessmen bought the goods, bottled them, labeled them as "Shi Die Oyster Sauce" or "Jinshanzhuang Super Oyster Sauce" and resold them abroad as genuine products, which were very popular with foreign gourmets and sold a lot. Many overseas Chinese who have returned to their hometowns have come here to buy a few bottles of oyster sauce for the holidays, or to give them to relatives and friends as warm gifts.