Determining the sex of the fish is difficult, as in some cases the females look the same as the males. And if you do not know the features that are characteristic of a given breed, then it is completely impossible. But you can still try to distinguish them, especially if it is very important to you.
Contact your seller if you are just looking to buy fish. Usually people who are more or less versed in fish trade in such stores. If they cannot explain to you who is male and who is female, then it is better to contact another zoological store.
Compare the shape and size of the fish. Often, females are somewhat larger than the opposite sex, as they carry future offspring. But there are also exceptions. If your fish have at least some visual differences, then fry will appear soon. Observe the fish periodically. If some suddenly began to increase in size, and the abdomen became rounded, it is most likely that these are females. You just have to wait a little to determine the gender of the aquarium fish.
Pay attention to the coloration of the aquarium fish. Usually, the color scheme of males is brighter and more saturated - from it you can determine the gender of aquarium fish. Females in most cases have an outstanding appearance. But it all depends solely on the type of fish, so you may be wrong.
The fins and tail of males are somewhat longer and brighter. Their color can change during the "mating" period: various blotches and additional pigmentation appear. This makes them more attractive to females. After spawning, the opposite changes occur.
Obtain specific literature on this fish species. In the book, you can read in detail about the characteristic sex differences. If you are not sure which species your aquarium pets belong to, check the store for their name. It is usually indicated on aquariums.
If you still cannot accurately determine the sex of the fish, but at the same time you noticed a number of differences, then just wait for the addition. Some fish species do not visually differ in sex, so do not be upset if exactly the same individuals swim in the aquarium. It is possible that they are heterosexual.
