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Guppy Fry 101: Care, Stages, Food, Tank Setup & More

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Even as an experienced aquarist, I know that growing guppy fry can be challenging. That is particularly true for those of you who are new to this hobby, as guppy fry raise many questions and have their own needs.

So, after years of experience, I decided to gather the most frequent questions into one article. In many cases, I will link to another article that I wrote so that you get the picture in detail.

Ultimately, in the last part of this article, I will list some essential tips that will help you care for your guppy fry. So, without further ado, let’s dive into it.

For those of you who are in a rush, here is a table that gathers some of the most crucial information on guppy fry:

Feeding frequency4-8 meals a day
Separation duration6-8 weeks
Survival rate0-40%
Tank size10 gallons
Temperature74-82º F (23-28º C)
Hardness8-12 dGH
Ammonia0 ppm
Nitrites0 ppm
Nitrates<20 ppm

Also Read: Guppy Care Guide

What Do Baby Guppy Fry Eat?

This is what guppy fry usually eat: 

  1. Brine shrimp 
  2. Flakes 
  3. Freeze-dried bloodworms 
  4. Egg yolk paste 
  5. Microworms 
  6. Vegetables 
  7. Hikari 
  8. Beef heart

Guppy fry can eat different and varied foods. As they are just starting to grow, it is essential to provide them with both protein and vitamins. As a rule of thumb, I suggest mixing one type of vegetable with one type of meat.

Still curious? Click here for more information on what do baby guppy fry eat. I also explained the right way to feed guppy fry and included some practical videos to help you do this the right way.

How Often Should I Feed Guppy Fry?

When they are just born, guppy fry should be fed four to eight meals a day, in three to four hours intervals. After two months, that frequency can be reduced to three or four meals each day. After five months, you can feed the fry one or two meals a day.

In each meal, I suggest giving the fry what they can finish within two to three minutes. More than that would ruin the water chemistry and cause ammonia to spike. As it can be exhausting to feed guppy fry so frequently, many aquarists prefer using an automatic feeder.

Still curious? Click here for more information on how often to feed guppy fry. In that article, I also discussed whether you could overfeed or underfeed guppy fry and provided my personal recommendation for an automatic feeder. 

Can I Leave Guppy Fry In The Tank?

Guppy fry can be left in the community tank, but only a few will survive without taking the proper measures. To ensure that some will survive, one should provide them with hiding places, such as plants and decorations. Without those, it is better to use a breeder box or a separate tank.

As you will see later on, most guppy fry won’t survive, even if kept in a separate tank. In a community tank, the survival rates can drop up to zero. Hiding places will keep the fry out of their parents’ sight, which will gladly eat them alive.

Still curious? Click here for more information on whether you can leave guppy fry in the tank. I made sure to discuss some practical ways to stop adult guppies from eating their fry. I also shared the set of decorations I have bought in the past.

How Long Do Guppy Fry Need To Be Separated?

Guppy fry should be separated for at least 6 to 8 weeks. At this stage, they will reach the size of one to two inches, so they are too big to fit in their parents’ mouths. In aquariums that hold large and aggressive fish such as cichlids, guppy fry should be separated for four months.

You can keep guppy fry separated by using a divider in their original tank or an entirely different container. I personally suggest installing a divider. That will ensure the fry will remain in a cycled tank without ammonia and nitrites spikes.

Still curious? Click here for more information on how long do guppy fry need to be separated. In there, I elaborated on whether you should use a breeder box or a breeder tank and shared a video on how to make your own aquarium divider.

How Many Guppy Fry Will Survive?

These are the survival rates of guppy fry, with correlation to their growing environment:

  • Main tank: 0-15%
  • Breeding boxes: 15-25%
  • Breeding tanks: 30-40%

When the guppy fry grow in breeding tanks, they have the highest survival rate. That is because breeding tanks are not stressful as breeding boxes and don’t occupy adult fish that can quickly eat the fry.

Still curious? Click here for more information on how many guppy fry are expected to survive. In this article, I mentioned some practical tips that will help you increase the survival chances of your guppy fry.

How Long Does It Take For Guppy Fry To Grow?

It typically takes four to six months for guppy fry to grow and reach full size. At two months, guppy fry reaches sexual maturity and can reproduce. Also, after two months, they can stop being separated from adult fish.

After half a year, your guppy fry will stop growing and be considered adults. But that doesn’t mean they should be separated for this long. They will also breed much sooner than that.

Still curious? Click here for more information on how long does it take for guppy fry to grow. I also shared some valuable tips to ensure your guppy fry grow at the right pace.

What Are The Guppy Fry Growth Stages?

These are the guppy fry growth stages:

  • Stage 1 (days 1-30) – The fry are 0.6cm in length, and their skin is fully transparent. 
  • Stage 2 (days 30-60) – The genital organs are seen, and the fry is subtly colored. 
  • Stage 3 (months 2-4) – The fry reach sexual maturity and present intense colors. 
  • Stage 4 (months 4-6) – The guppies become adults and start reproducing quickly.

The growth of guppy fry is pretty fascinating, especially in their early stages. The guppies are entirely transparent at the start, and you can sometimes see their spine. 

After a month or two, you’ll see the gravid spot, which tells you that the fry is a female. Males can be identified by their colors as it is difficult to see their genital organs when they are young.

Still curious? Click here for more information on the guppy fry growth stages. I made sure to include some beautiful pictures that illustrate each stage. I also included a Youtube video that demonstrates how guppy fry grow, week by week.

Do Guppy Fry Need An Air Pump? 

Guppy fry usually require an air pump. They can survive without them, although air pumps make the environment more sustainable and prevent oxygen deficiencies. An air pump will also encourage the growth of plants and algae, which are essential for guppy fry.

Guppy fry are pretty vulnerable, especially in their early stages. They are less likely to sustain oxygen deficiencies or toxins, so installing an air pump is necessary. It will allow your guppy fry to breathe comfortably and increase their survival chances.

Still curious? Click here for more information on whether guppy fry need an air pump. Besides listing the advantages of having an air pump, I made sure to give my personal recommendations on which one you should get.

What Can I Do With Unwanted Guppy Fry?

This is what you can do with unwanted guppy fry: 

  • Let their parents eat them. 
  • Introduce predatory fish to your tank. 
  • Give the fry away for free. 
  • Sell the fry to a local store. 
  • Flush them down the toilet (not recommended). 
  • Euthanize the fry. 
  • Move the fry to a large tank so they can’t reach the food.

Not everyone likes the idea of having guppy fry. As pregnant guppies can have up to 80 babies at a time, growing them can be time-consuming. If that is your case, bear in mind that leaving them with their parents is the natural solution.

Still curious? Click here for more information on what you can do with unwanted guppy fry. I also elaborate on a pretty exciting option: selling the fry for profit. Surprisingly, some fish owners will pay up to $5 per fry.

Is It OK To Let Guppies Eat Their Fry?

It is considered OK to let guppies eat their fry because this is what also happens in nature. It won’t cause any harm to the adult fish or the water chemistry. Some aquarists even consider guppy fry as feeder fish, which are grown for the purpose of feeding other fish.

Some people feel guilty when they see adult guppies eating their fry. But there is no reason to feel this way. Guppies, like other fish, will eat whatever fits in their mouths, including their own babies. This is how nature goes.

Still curious? Click here for more information on whether it is okay to let guppies eat their fry. It is a subjective matter, but this article will shed some insights on how natural and innocent this process is.

How Do You Care For Guppy Fry?

Guppies have an average lifespan of 2 years.[1] But they won’t make it to three years unless you create a conducive environment for the species in your aquarium. You have to maintain the following conditions to keep them happy:

1. Choosing The Right Tank

This has to be your first consideration. The aquarium will host your guppies for the entirety of their lifespan. Therefore, you can’t concern yourself with other factors until you find a suitable aquarium. Keep the following in mind:

  • Size

Guppies can grow to a size of 2.5 inches. Take the guppy size into account when you select a tank. The creatures require a minimum of five gallons. 

But experienced aquarists will encourage you to aim for ten gallons, especially if your goal is to make the fish as comfortable as possible.[2] Don’t forget the guppy’s breeding habits. Forty gallons sounds like a lot of water for a guppy. 

However, these creatures can produce 200 fry per month. It won’t take them long to overwhelm a 5-gallon tank, especially if you’re taking deliberate steps to protect the babies from their parents.

Start by determining the maximum number of guppies you want to rear in the future and find a tank that can accommodate them. 

You should also consider other objects, as guppies are not the only inhabitants of the tank. You must add plants, ornaments, filters, and pumps. 

A seemingly large tank can become crowded once you add all these amenities. If you’re new to aquariums, find experienced aquarists on the internet. 

They know what the average aquarium should hold. Depending on the number of guppies you want to rear, they can recommend a suitable size. 

  • Width

The width also matters. Oxygen enters the tank through the gaseous exchange that happens at the surface. Oxygen deficiencies occur all the time in aquariums, resulting from inefficient filters, poor maintenance routines, crowded conditions, and the like.

You can counteract oxygen deficiencies before they occur by getting a wide tank that increases the size of the water surface that comes into direct contact with the air.[3]

Many aquarists are tempted to buy narrow tanks because of their stylish look. But narrow tanks limit the water surface area and reduce the amount of oxygen entering the water. 

A broad tank also creates more room for the guppies to explore. You have more space to add rocks, driftwood, pots, etc.

  • Material

The material won’t affect the health of your guppy fry inside the tank. However, it can impact their safety long-term. Glass is an excellent material for aquariums.

But unless you bought the thickest and most expensive models you could find, the aquarium can shatter if it falls or if a hard object strikes the walls.

The last thing you want is for your fish to die on the floor while gasping for air. Acrylic is a better option because of its superior durability. Though, it has its disadvantages.

2. Adjusting The Water Parameters

The pH refers to the acidity or alkalinity of water. The scale ranges between 0 and 14. Water above 7.0 is alkaline, while the opposite (pH less than 7.0) is acidic. Pure water is neutral.

Guppy fry can tolerate any pH between 6.8 and 7.6.[4] They are adaptable, capable of surviving in various water conditions. The stability is actually more important than the pH (so long as the pH falls within the range mentioned above). 

To measure the pH, I suggest getting a testing kit. I personally got the API FRESHWATER MASTER TEST KIT (link to Amazon). That bundle also measures the ammonia, nitrates, and nitrties, which should be kept at 0 ppm.

Some kits use strips to test the pH. Others require the aquarist to add small drops of chemicals to a small cup of aquarium water. 

If you’ve never tested the pH and you don’t know how to interpret the results, take a sample of your water to a local fish store. Though, most test kits have instructions that can guide you accordingly. 

If the pH is too high, you can lower it using the following methods:

  • Leave tap water to aerate in a bucket. This will lower the pH within a few days. Do this a few days before you change the water.
  • Add live plants.
  • Use water conditioners like Seachem Prime (link to Amazon). This product will also prevent toxins from spiking in the future as it acts as a buffer.
  • Add Driftwood.
  • Increase the CO2 in the aquarium.

What if the pH is too low? You can increase it using the following:

  • Add baking soda (One teaspoon for every five gallons). Keep the fish out of the water for an hour after adding the baking soda.
  • Add coral or limestone to the substrate. You can replace the substrate altogether.
  • Add seashells (Two per gallon).
  • Remove the driftwood.
  • Make sure you boil the decorations before adding them to the tank. You can do the same thing whenever you clean the tank. This prevents the tannins from influencing the pH.[5] 

3. Setting The Proper Temperature

Guppies are tropical creatures that require temperatures ranging from 74 to 82 degrees F.[6] Try to avoid extremes. Guppy fry can live in water as cold as 63 degrees F and as high as 87 or even 90 degrees F, but they won’t be happy.

The creatures won’t die, but you shouldn’t allow the temperatures to exceed these parameters. Cold water is problematic because it slows the guppy fry’s metabolism, making the fish sluggish and affecting its appetite.

Guppies in cold water are more susceptible to diseases. But hot water isn’t any better. Besides increasing aggression and metabolism, hot water will introduce oxygen deficiencies because hot water cannot hold as much oxygen as cold water.

That is why I suggest buying a suitable heater. Do not leave the guppies at the mercy of the ambient temperature. A heater allows you to control the temperature in the aquarium with greater accuracy.

I personally went with the Orlushy Submersible Aquarium Heater (link to Amazon). After testing dozens of them, that is probably one of the most reliable aquarium heaters.

But if you live in a hot region and ambient temperatures keep spiking during the summer, don’t hesitate to switch the heater off to prevent the water from overheating. You can also switch the lights off. Artificial lighting can raise the temperature to dangerous levels. 

4. Picking The Right Plants

Guppy fry need plants. Live plants improve oxygen levels because they produce oxygen and consume CO2 during the day. One way of aerating water in aquariums is to add more live plants.

Artificial plants attract aquarists with busy schedules because you don’t have to keep them alive. Additionally, you don’t have to worry about herbivores eating them.

But if you’re willing to look after them, live plants are the superior option because they emulate the guppy’s natural habitat. And before you ask, the answer is no. Guppies do not eat plants.

They may nibble on the leaves to reach the algae. But they have no interest in consuming the plants themselves.

And more importantly, guppy fry depend on the cover they provide to escape predators. Guppy fry can survive to adulthood in a community tank if they have dense foliage that provides an abundance of hiding places.

Your selection will depend on what you want. Different plants have different attributes. For instance:[7]

  • Java Moss proliferates quickly and is easy to care for. Java moss will survive in low to medium light conditions. 
  • Flame Moss is shorter than Java Moss, but it is just as easy to care for.
  • Water sprite is a gorgeous plant that can float in the water or survive in a substrate of sand (or gravel).
  • Water Wisteria is another fast grower. On top of providing hiding spots for baby guppies, it will clean the water.

5. Choosing The Right Tankmates

Guppy fry cannot reach adulthood unless you surround them with suitable tankmates. For fish to qualify as suitable tankmates, they must satisfy three criteria:

  • Size – You need fish whose size matches that of the guppies. As opportunistic feeders, fish will eat anything that fits in their mouths. 

Additionally, they are more likely to bully smaller, weaker creatures. Therefore, you are better off giving the guppies neighbors that are neither too big nor too small.

  • Temperament – A smaller fish can still make a guppy’s life miserable if it has an aggressive streak that encourages the creature to nip at the fins of its neighbors. You need friendly fish with social personalities.
  • Tank Level – Where possible, find bottom-dwellers that are more likely to steer clear of the guppies.

Some suitable guppy tankmates include Cherry shrimp, Kuhli Loaches, Nerite snails, and Bristlenose Plecostomus.[8]

But as a rule of thumb, I recommend keeping the guppy fry in their own tank until they reach a size of one inch. That usually happens after six to eight weeks. 

6. Keeping A Clean Environment

Guppy tank maintenance has two significant components. First of all, you should install a filter. Make sure the strength of the filter matches the size of the tank. 

Otherwise, a weaker filter will allow stagnant, oxygen-deficient spots to form because it cannot agitate the water adequately.

When it comes to guppy fry, it is better to cover the intake valves with a sponge to prevent them from sucking the babies into the filter.[9]

But the filter won’t help your guppies unless you change the water every week. Replace at least a quarter of the water. Use conditioners to treat the new water.

7. Feeding Them Properly

Adult guppies should eat 2 to 3 times a day for two to three minutes at a time. They are omnivorous creatures that can eat both animal and plant matter. However, as I already mentioned earlier, guppy fry should be fed more frequently.

The feeding intervals mainly depend on the guppy fry’s age. It is better to use an automatic feeder when they are just born, as they’ll eat up to eight times a day. But as a rule of thumb, it is better to underfeed than overfeed them.

Another important rule is to maintain regular mealtimes. Don’t feed the guppies simply because they look hungry. Fish will continue to eat if you keep feeding them. This is why overfeeding and its related consequences (such as constipation) are so common.

Also Read: Breeding Guppy Fish

Pro tip: If your guppies breed frequently, you’ll need to know a little more about that process. Feel free to check my complete guide on pregnant guppies.

Summarizing The Recommended Gear For Guppy Fry