What Are the Guppy Fish Growth Stages?

The survival rate of the Guppy fish in aquariums is dependent on how you keep them out of danger and maintain good conditions for their growth. For this, you need to know about the details of the Guppy fish growth stages that enable you to take adequate measures.

What Are the Guppy Fish Growth Stages? There are four distinct guppy fish growth stages. The four stages are, Guppy fry, Guppy Juvenile, Young Guppies and Adult Stage guppies. The characteristics vary at each stage

What Are the Guppy Fish Growth Stages

Therefore, you need to take into account the various threats to their survival. Moreover, you have to also take care of creating the right conditions for their proper growth.

We will consider the factors that create a healthy environment to ensure that your aquarium has big, healthy and colourful Guppies.

What Should You Know About Guppy Fish Growth Stages?

Guppies Size

This is very important to decide the size of the aquarium. So just how big do the guppies get? How soon do they reach there full growth?

For this, you would do well to remember the formula five-five. This, in short, indicates that the size of the fish is 5 cm and it reaches the size within 5 to 6 months.

The female of the species reaches its full-grown size of 5 cm (2 inches). In striking contrast, the males are shorter in length, with a maximum of 3.8 cm (1.5 inches) only.

The 4 Guppy Fish Growth Stages

  1. The Guppy fry Stage
  2. Guppy Juvenile stage
  3. Young Guppies
  4. Adult Stage guppies

Important Aspects of the Guppy Fish Growth Stages

The Guppies do not have a larval stage as they do not lay eggs. Instead, they are livebearer fish. After fertilization, the baby guppies develop within the mother’s body for approximately 30 days.

Guppy Fries

fry Guppy Fish

The babies, or the Guppie fries, are capable of swimming freely right from the time they are born. They also have an acute survival instinct and are seemingly aware that their life is at threat in the hands of the other full-grown fish.

Therefore, they look for hiding places until they are strong enough to fend for themselves. Their bodies are small – just about 0.6 mm (1/4 inch) in length. Also, they are very frail at birth but become bigger and stronger within a few hours.

Once they are born, the first thing they do is to look for a place to hide. This is because they are at risk of being eaten by adult guppies and the other bigger fishes.

It is for this reason that you should try to design the aquarium which has a lot of plants and rocks that give them hiding places.

You may also consider separating the pregnant female adult Guppies. Similarly, keeping baby guppies away from other fish for a week in a breeding box increases their survival rate drastically.

You can thereafter release them into the main tank along with other fish.

The Guppy Juvenile Stage

The baby guppy fry becomes a juvenile in about a month. The most distinguishing factor besides their larger size is their gaining color.

Besides this, you will also be able to distinguish their sex by the relative size as well as the easily visible gravid spot in the females. On the other hand, males have smaller tails. Besides, you can also observe their gonopodium start forming.

The juvenile Guppies are up to 2 cm (3/4 inches) in length in about a month, during which they mature sexually and become young guppies.

Young Guppies

Guppy Fish Growth Stages

This is the stage between the Juvenile and adult stages and what we can call as the growth stage to adulthood. During this stage, they grow to their full size and brilliant shades of colors. Therefore, a nurturing environment during this stage determines their life span, as well as their health in the adult Stage.

Your care and attention by giving them the best quality aqua-food and clean water make a lasting difference in their life span. Not only that, but it also makes them reproductive and active for a longer time. Guppies reach sexual maturity in 3-4 months. Thereafter, it is a good idea to separate the males from females, until they reach the adults’ stage.

The Adult Guppy

Guppies reach their adult stage around the time they are 6 months old. At this stage, their size reaches 4 to 6 cm (1.5-2 inches) in the case of females. This is smaller in the case of male guppies.

Their growth rate stops significantly and their activity level reaches their peak, depending on the aquarium size, food, clean water and of course, their genes.

Guppies live actively around 2 to 3 years and given the right conditions are known to almost till 5 years. However, adult guppies are generally infertile and unable to reproduce in about 2 years.

Important Hints for Breeding

The growth rate of young guppies depends upon their health. Providing a high protein diet makes them stronger are they attain sexual maturity in about 4 months. This is one important reason to keep the young males and females apart till they are mature enough.

When they are very young and small female Guppy produces only 4-10 fry. At the same time, a female 6 to 8 months old guppy can easily drop as much as 100 fries. Although the quality of fry is not affected it is better to wait for the female to grow up into adulthood to give a higher number of fry.


Whatever be the guppy fish growth rates, you should feed them a wide variety of protein-rich food to keep the guppies colorful and healthy. Moreover, their main food should be in flaky form for smaller guppies during their fry and juvenile stages.

Also, do keep in mind that when breeding guppies, it is highly recommended to separate males from females when they are 5-6 weeks old. They should be kept in separate tanks until they are 5-6 months old. Besides the quality of fry, another advantage is that at this age of easier to select the robust males and females that are fit for reproduction. This way you can choose only the best ones for breeding.





Hello, I'm Jason. I'm the guy behind HelpUsFish.com. I volunteer at my local fish shop and I created this site to offer tips and advice on the fish I care for.