First of all, a big belly is an obvious feature.

And you need to know the date of its last production, which is easy to distinguish, because there is about one nest every month and it will be isolated in the third week. There are also some special circumstances that may not last for a month (such as incomplete production in the previous month, and some will be remake halfway), so it depends on other aspects. The normal genital foramen is round, and it will appear square when it is born.

Second, we need to know whether guppy is fertilized.

Because guppies will be denatured under special circumstances or mutation, (this kind of fish is called "Erba Dao" in Northeast China. What do you call it there? So first of all, it depends on whether the ovaries (dark spots) of the female fish are obvious.

Thirdly, females seldom or never eat food when they are about to give birth, so we should pay attention to whether some pregnant females grab food as before when feeding bait.

Fourth, the female who is about to give birth will stay away from the fish and stay alone in the corner. We should also pay attention to such a pregnant female fish.

(Introduction of information about guppy):

Poecilia reticulata, commonly known as peacock fish, is also called anchovy, rainbow herring, rainbow herring, peacock fish and so on. It is a tropical fish, belonging to the genus Ciliates of Ciliatedae. The size and color of male and female fish are quite different. Adult male fish is slender and 3-4 cm long. The adult female fish is about 5 cm long, and the tail stalk and fins account for more than 1/3 of the whole body, and each fin is shorter than that of the male fish. It is much worse than the male fish.

Peacock catfish is a small omnivorous fish. They have strong adaptability to the environment, distributed in the downstream of rivers, lakes and ditches in some tropical areas, and their wild habitats are diversified, mainly distributed in freshwater basins and lakes and swamps. Can tolerate dirty water, with clustering. Widely distributed. Originated in Venezuela, Guyana, West Indies, northern Brazil and other places in South America,

As an ornamental fish, guppies have been introduced to all countries in the world. Moderate temperament, can be mixed with moderate small and medium-sized tropical fish, usually lively and active, short life.

Under artificial cultivation, many strains have been produced, the most representative of which are dress, grass tail, metal, snake king, lace, Yinhe, Medusa and so on.

Reference link: Baidu Encyclopedia: Peacock Fish