Sam Borstein's Cichlid Page

Poecilia reticulata
Peters, 1859

Guppy, Millionfish

Neon Blue Tuxedo Guppy
Above: Two male Neon Blue Tuxedo Guppies. Photo by Sam Borstein.


Genus- Poecilia= many colors (Greek).
Species- reticulata= reticulated (Greek).


The Guppy is a classic and is a common fish in the hobby. If you go into a pet shop and they don't have Guppies, you wonder how they can make money. The Guppy is popular because it is easy to keep, breed, and through line breeding, extremely colorful. Many peoples first fish were Guppies.

This fish is also popular because they give live birth to their offspring.

Here are some variants. These all come in different colors:
Yellow Micariff Guppy
Yellow Micariff Guppy
Red Fin Guppy
Red Fin Guppy

Sunset Guppy
Sunset Guppy

It is relatively hard to find wild Guppies, but if you do, get them, they are just a beautiful. It is important to note that the Endlers Livebearer is not a Guppy, but rather a closely related species and should never be kept with Guppies as the two will hybridize.


This fish is found in lakes and pools of South America.

Size, Maturity, and Sexual Dimorphism:

Size: Males- 1.5 inches, Females- 2.5 inches
Maturity: 1 inch
Sexual Dimorphism: Males are smaller than females and have more color and more ornate fins. Males have a gonopodium.

Guppy Females
Above: A female Guppy. Photo by Sam Borstein.


Guppies are easy to care for. They are really undemanding fish. They are peaceful, so you really only have to be wary about tank mates. Don't put them with highly aggressive fish or fish much larger than them.


These fish will eat anything. A mixed flake is recommended.


This fish is very easy to breed. Males use their gonopodium to fertilize the females. Females will swell up with the babies inside them and after about 3 weeks, give birth.

The fry do have umbilical cords, but lose them after birth. Fry grow fast, and by three weeks are sexually mature. The parents may or may not eat the fry. The fry are easy to raise and will gladly eat baby brine shrimp and crushed flake. Spawns can be large with large females having an average of about 30.


Guppies are nice fish for beginners. I like the wild types, but they can be hard to get. These guys are an easy fish to keep and breed. If you are thinking about starting keeping fish, try Guppies.