How Many Guppies Can You Keep in a 10 Gallon Fish Tank? {The Truth Behind Guppy Tank Sizes}

Guppy lovers worry about tank size or the number of guppies they can keep in an aquarium.

How many guppies can you keep in a 10 gallon fish tank?

In this article, we’ll find out if 10 gallons is enough for guppies and if you need more space to keep more of these super popular fish.

How Many Guppies Can You Keep in a 10 Gallon Fish Tank?

You can keep 1 inch of fish for each one gallon of water.  The average size of a adult guppy is 1 inch to 1.5 inch, so in a 10 gallon tank you can keep 7 – 10 guppies.

If you are looking to purchase a 10 Gallon Tank I recommend you check out the tanks on Amazon. 

How Many Guppies in 10 Gallon Fish Tank

How Many Guppies Can You Have In A 10-Gallon Tank?

Female guppies are larger than males. 10 of them with a 2:1  female to male ratio fit in a 10-gallon tank.

However, a female guppy is just 2 inches long. You should only retain five females per ten gallons of water if you only intend to keep females.

Can I Breed Guppies In A 10-Gallon Tank?

Yes, you can, but it is recommended you follow the rule. One inch size of guppy to one gallon of water, but do everything to avoid overcrowding in the aquarium.

  • Get a standard bio filter media for filtering.
  • You must ensure there’s fast-growing plant in your tank/aquarium
  • Make changing water once a week your habit. 

How Do I Prevent Overcrowding In My Guppy Aquarium?

At this point, you may have to scarifice your fry for the good of your adult guppy populatiom.

  • Just keep male guppies.
  • Do not keep any male guppies.
  • Male and female guppies should be kept in separate tanks.
  • Fry guppies can be left with adult guppies.
  • Eliminate or lessen any hiding places.
  • Put your guppy fry in a pond outside

Some of these suggestions may not sit well with you, but overcrowding can cause more damage to your tank’s ecosystem that a few deaths.

YouTube video

Identifying Between a Male and Female Guppy Fish

Male and female guppies have different facial features

  • Males are more colorful, smaller, and have thinner anal fins (gonopodiums).
  • In females, there is a black area behind the gonopodium that gets darker during pregnancy.

Males can detect pregnancy in females. They will briefly interact with females and transmit spermatophores to them.

The female guppy can conceive several times with that sperm. The young will develop inside the egg, which is inside the female’s body. Guppies are considered ovoviviparous because of this.

How Many Gallons Do You Need for 2 Guppies?

Guppies typically reach a length of 2 inches. The smallest aquarium I advise is a 5-gallon tank for a 2-3 guppies.

However, I still think a 10-20-gallon aquarium might be more suitable in the long run considering how fast they multiply. You will probably enjoy the experience and most likely wish to get more. That’s what happened to me.

When Do Guppies Reach Full Size?

With proper nutrition, they’ll grow to their full size in six months.

When your guppies are young and developing, an ideal tank temperature is at about 80 degrees Fahrenheit.

In order to slow down your guppies’ metabolism and keep them more comfortable as they age, you should lower the water temperature a few degrees after they get older.

How Often Do Guppies Reproduce?

Guppies normally breed every 30 days, giving birth to 20 times or more during the course of their lifetime. Guppies in high-predation areas begin reproducing earlier than those in low-risk areas.

This is assumed that guppies realize they are in danger and seek to multiply to keep their population thriving despite adverse or threatening situations that could lead to their early death from larger predators.

How Many Guppies In A 20 Gallon Tank?

One gallon of water for every inch of guppies is the typical rule to determine how many to put to a tank. A two-inch guppy thus need two liters of water.

  • 10 to 15 guppies are the perfect amount for a 20-gallon tank.

Although keeping 12 guppies in a fish tank is perfectly feasible, it is not advised for beginners. It’s not a good idea to start with a large quantity if you’ve never kept fish, especially guppies. Start small and increase slowly.

How Many Guppies in a 55 Gallon Tank?

The most likely amount for a 55-gallon tank is between 20 and 25 guppies.

To guarantee that they are entirely comfortable, you should try to reduce the quantity.

It is preferable to have a few less than a few too many since having too many can lead to a variety of issues, from overcrowding to water chemistry issues.


The recommended quantity of guppies in a 10 gallon tank is less than 10. Try to keep in mind that the precise number will depend on their gender and size. Retain males and females in a 1:2 ratio if you decide to keep them.

Because females are always larger than males, it is necessary to keep fewer of them.

Guppies are incredibly simple to care for and reproduce quickly. They are great fish for beginners and guppy enthusiasts combined.

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