They're a minority in nature. Few species are liveable. They are found in North America and Central America. They are the most popular among beginners, including Lebistes or Guppys, platys, Mollys and Swords. The males have gonopodium, an adaptation to retain the female, copulate and thus fertilize the eggs inside. They are easy to care for and reproduce.
Xiphophorus helleri
It is one of the most popular and genetically altered tropical aquarium fish in the world. The only wild variety is green. There are other varieties (crossed in aquarium with Platys) such as: lyre, blood red, pineapple orange and marbled. It is usually in the middle or upper area of the aquarium and seeks shelter in the plants. They are active but do not bother their peers, characteristic that makes them ideal for living in community aquariums. It's good to have couples of similar size.
Xiphos are ideal if you have an interest in reproduction. It will distinguish males by the extension of its tail fin, at its bottom, in the form of a sword. Its body is thinner and the fins are straighter. The female is more plump and its fins, especially the caudal, are very rounded. The male fertilize the female with its gonopodium in the ovoppositional tube. Sometimes her sperm lives long enough in the female to have two or three litters of offspring. Females can grow to have more than 120 offspring in a month. The presence of plants will serve as a refuge for the fry. You can also remove the female before childbirth. Then a paridera aquarium, with water from the main aquarium, will ensure a greater number of fry safe.
Poecilia reticulata
It is one of the most popular fish in the whole world of aquarianism. It is easy to care for and reproduces endlessly. The Lebistes or Guppys reach maturity in just 4 months, so they reproduce constantly, generation after generation. A female can give birth to 40 fry per month. Males are extremely colorful, while females have small fins and no color on their body.
The Molly velifera can be recognized by its large fins. The distinctive feature is its dorsal fin, which has 5 rays more than that of the common molly (Poecilia latipinna). For males to develop this dorsal fin, it will need to accompany them with several females and provide them with a very large aquarium. They develop better with elevated temperature (26º) and if a teaspoon of salt is added to the water. Make sure that this last action is not harmful to your aquarium mates.
It is one of the ideal fish for those who start caring for fresh water tropical fish. There are many varieties of colors and shapes of fins. We can mention varieties such as Molly albino, Balloon, Marbled, Mexican, etc. It adapts perfectly to the community aquarium. It is of peaceful behavior and coexists well with many species in the same fish tank.
Mollys reproduce with great ease. You can identify males by their stylized body. Females are larger and round. For a month the fry are gestated inside, approximately 90 to 110 young. He must feed his young with live food and algae.
xiphophorus maculatus
It is another ideal fish for those who start caring for fresh water tropical fish. There are many varieties of colors and perfectly fits the community aquarium. It is very peaceful and there are many species with which the fish tank can share. They reproduce easily. You can identify males by their gonopodium badge. Females are more corpulent and gestate about 80 fry inside for about a month.
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