Guppies often reach their adult size of approximately 2 inches in 6 months.
If you’re breeding guppies for the first time, you might not be too sure whether they’re growing at the right rate or not. It’s not surprising at all that new breeders wonder how fast do baby guppies grow?
In this article, we’ll answer this question in detail. In addition, we’ll address a bunch of other questions you might have. For example, what are the different growth stages of guppies? Why aren’t they growing? And how to make them grow faster?
So, How Fast Do Baby Guppies Grow?
Baby guppies are around a quarter of an inch at birth. Proper care and good nutrition should keep them growing at a healthy rate till they reach adulthood.
By the end of six months of diligent water changes and nutritious meals, female guppies should reach an ideal length of 2 inches. Males are a bit smaller, and we’re usually happy to see them becoming an inch and a half at adulthood.
What Are the Growth Stages of Guppy Fish?
Guppies keep their baby fish inside their tummies post fertilization, which is scientifically known as ‘livebearing’. Thus, the baby guppies miss out on the larva stage entirely.
Fertilized eggs remain inside the mother for about a month, then they’re ready for birth. Initially, they’re weak, vulnerable, and defornmed. At this stage, they’re barely a quarter of an inch long.
They naturally look for a hiding place. Then, in a couple of hours they emerge, ready for feeding.
Juvenile Guppy Fish
After a month, the tiny fry become larger, gain a bit of color, and their sexes start showing. This stage is critical in the guppy’s healthy growth, as they need good quality food, clear water, and an aquarium of a suitable size.
By the end of two months, they should reach a length of ¾ inches.
Young Guppy Fish
Young guppies have a higher need for a varied diet than a high-calorie one. So this is a good time to introduce more proteins and plants. Brine shrimp, plankton, and spirulina are ideal for these young guppies.
It’s worth noting that young guppies are quite ready for mating. But that usually takes up a lot of energy and slows down their growth curve. You might want to keep the ladies separated from the gents at this stage.
At the onset of the sixth month, we consider them adult guppies.
Adult Guppy Fish
Adult guppies reach their full size and rarely grow beyond that size. Interestingly, guppy females are quite larger than guppy males, with a half an inch difference between the two genders.
The guppy’s lifespan is 3 years on average, but they become incapable of breeding at two years of age.
How Long Do Guppy Fry Need to Be Separated?
The fry is viewed by the adult guppies as delicious food. Also, they have different feeding and care requirements than adult fish.
Thus, they need to be transferred to another aquarium at least until they become young guppies. It’s best to wait till they become adults.
Why Are the Baby Guppies Growing Slowly?
Guppies are often healthy eaters and they typically grow quickly. There are some exceptions though, and we occasionally see guppies that don’t seem to get bigger at all.
There are some genetic factors that might affect the guppies’ growth rate and ultimate size, but more commonly, the care routine of the fish might be the real cause.
The main causes of guppies’ slow growth could be any of the following:
- The guppies aren’t getting enough good quality nutrients
- The food isn’t sufficiently varied and lacks micronutrients
- They aren’t getting treats from time to time to stimulate their palate
- The water sits in the pool too long till it becomes contaminated
- The water parameters need adjustment
- The aquarium is too tight for the guppies
- The aquarium is much too large that they can’t find food or shelter
How Can I Make My Guppy Fry Grow Faster?
If the type of your guppies isn’t genetically inclined to stay small, then you can take a few measures to boost its growth. Here are some tried and true methods to make your guppies grow faster.
Change the Guppies’ Water Frequently
Guppies are known for having a healthy appetite and excreting frequently. That’s why their water is often soiled with remaining food and wastes. If this contamination is left for more than a day, this could slow down the guppies’ growth, or even make them sick.
Some breeders change the aquarium water fully at the end of every day. This might require some effort, so if it’s not possible, at least do partial changes twice a week.
Give the Baby Guppies Nutritious Varied Food
Adult fish need food to maintain their daily needs of activity, but that’s only a fraction of what the fry need. Baby fish need to survive, grow, and build strength.
Dry food is often sufficient for adult guppies, but it barely scratches the surface for fry. Live food is necessary, and it’s preferable to offer it on a daily basis till the baby guppies become young adults.
Choose the Right Aquarium Size
The guppies are extremely small when they first come out of their mother’s belly, to the point that many breeders keep them in tiny containers.
This might be acceptable for a day or two, but after that, the fry’s growth slows down for no apparent reasons. Thus, they need to be transferred to a bigger aquarium.
The new aquarium shouldn’t be too big either. If the volume of the water is huge compared to the size of the fish, the fry needs to swim a lot to find food or a hiding place.
This would use up plenty of the baby guppies’ energy, and it would be hard for them to grow. Additionally, the extra-large surroundings and required effort could easily stress the fish out.
It’s recommended to give guppies under a month old half a gallon per fry. After that, a gallon per fry is the right size.
Watching baby guppies go from one growth stage to the next is such fun. They change in size, color, shape, appearance, and even in behavior.
It’s preferable, of course, to know how fast do baby guppies grow. This allows you to provide the best care for these fish, in addition to adjusting your expectations.