Cobra Guppy

Cobra Guppy

General Information
Scientific Name Poecilia reticulata
Minimum Water Size 5+ gallons (18.92+ liters)
Ease Of Care Easy
Average Lifespan 4 years
Temperament Peaceful
Approximate Adult Size 2.5 inches (6.35 centimeters)
Water Parameters 64-82 degrees Fahrenheit (17.77-27.78 degrees Celsius), 10-30 KH, 5.5-8.0 pH
Diet Omnivore
Native Region Central America to Brazil


The guppy, or also commonly known as the millionfish, is one of the most popular and common fish that is kept around the world. Not only do many begineers pick this fish to be in their setup due to their striking colorations and peaceful behavaiour, many experts also keep these fish as well. Males will have more vivid coloration due to them attempting to show off to all and any females, while females will have a slightly duller coloration and not so vivid colors. In most cases the female will appear to be slightly bigger body wise than the male as they have to hold within them up to hundreds of fry at any given time in their lifes, however the male will always have bigger and longer finage than any female regardless of strain.

Being the most common type of fish that is kept in various setups, there are several different types of strains which include them having brighter colors, various color elements, lonher tails, tails that are split into two parts, and even them having patterns such as a leperad pattern throughout their body. Sadly due to these strains being introduced through interbreeding, many of the current guppies that are on the market today have a very weakened immune system and/or genenic profile which can lead to fry being disformed or having issues later on throughout their life.


All guppies are classified as being livebearers, which means that they give birth to living fry compared to others which will release eggs into the water column. In order to tell genders, we can look at the anal fin of this fish. All males will have a tube like fin (called a gonopodium), where as the female will have a more round fin along with a pregnancy spot near this fin. It is to be noted however, that it can be almost impossible to tell the gender if the fish has not reached full maturity yet since these various signs will not be fully present or easy to tell apart. Due to their various colorations and finages, it might be very hard to tell if the anal fin is actually just a fin or a gonopodium. Thus, in order to be fully sure one can place the fish with our guppies and note their behaviour and interactions with the others. If they are following and trying to mate with the other guppies, one can fully conclude that the given fish is a male and not a female.

The male guppy will try to show off to the female by flashing it's tail around the female's body in order to allow for him to be able to mate. If the female does reject this, then you will see the female appear to try to swim away from the male as fast as possible. Any and all males will mate with any given female guppy, endler, and also molly within their setup, pregnant or not, which will release a type of sperm into the female. Shockingly, the female can hold a male's sperm for multiple months and is known to get pregnant, and release fry for up to 6 months without the help or addition of any males. The average gestation period for a female guppy is anywhere between 24-30 days which is mostly dependent on the diet provided to the mother during the pregnancy. Once the fry have been released by the mother, there will be no parental care provided from either the father or mother. In most cases, the mother will eat the fry right after they have been born or shortly after.

Many attempts have been made in order to crossbred a guppy and a molly as they are within the same family, however there have been very few successful fry being born and in most cases the fry will die at birth or be sterile if they survive. Such reports have outlined that it is required to use a female molly and a male guppy due to the fry size, while using a female guppy and male molly results in the death of the female guppy as she cannot hold the size of the fry.


In order to see the best coloration of any guppy, it is suggest that you give them a varied diet which is mostly based upon algae, then a plant based food (mostly what flakes are made of), and then slightly a meaty food such as pellets or live foods. During a female's pregnancy, algae will help with increasing numbers of fry being produced along with a more stable health throughout their first few months.