How-To Guide
Breeding Guppies
Guppies breed easily: a healthy male and females in a warm, planted tank will usually produce fry within a month. Females give birth to live young every few weeks and can store sperm. Provide dense plants or a nursery, feed fry small foods several times a day, and plan what to do with the extra fish.
How Guppy Breeding Works
Guppies are livebearers that use internal fertilization, and mature females give birth to free-swimming fry rather than laying externally developing eggs.
Sexing and Selecting Adult Guppies
Adult males are generally smaller and more colorful and have a modified anal fin called a gonopodium, while females are larger-bodied and have a fan-shaped anal fin.
Pregnancy, Sperm Storage, and Birth
Female guppies can store sperm and may produce multiple broods after mating, so a female acquired from a mixed-sex tank can give birth even after males are removed.
Setting Up for Birth and Fry Protection
Dense plants, floating cover, or a separate nursery can protect fry from adults, while cramped breeder boxes should not be treated as the only or automatically safest option.
Feeding Newborn Guppy Fry
Newborn guppy fry can usually take finely crushed prepared food, microworms, or appropriately sized live foods, and several small meals can support rapid growth.
Growing Fry Without Sacrificing Water Quality
Frequent feeding increases waste, so fry growth depends on mature filtration, regular observation, careful water changes, and enough space as juveniles become larger.
Population Control and Responsible Breeding
Guppies reproduce quickly, making it essential to plan for sex separation, grow-out space, future homes, and the long-term capacity of the aquarium before encouraging repeated broods.
Frequently Asked Questions
Can a Female Guppy Give Birth Without a Male in the Tank?
Yes. Female guppies can store sperm after mating and may produce later broods even when no male is currently present. Apply this within the stable water and husbandry conditions described for breeding guppies, rather than changing several breeding variables at once.
How Can I Tell a Male Guppy From a Female?
Males are usually smaller and more colorful with a gonopodium, while females are larger-bodied and have a fan-shaped anal fin. Apply this within the stable water and husbandry conditions described for breeding guppies, rather than changing several breeding variables at once.
Do Guppies Need a Breeding Box?
No. Dense plant cover or a separate nursery can protect fry, and confining a female in a small breeder box can cause stress if it is used poorly. Apply this within the stable water and husbandry conditions described for breeding guppies, rather than changing several breeding variables at once.
Will Adult Guppies Eat Their Fry?
They may. Providing dense cover or moving fry to a safe grow-out setup improves survival when the goal is to raise a large proportion of the brood. Apply this within the stable water and husbandry conditions described for breeding guppies, rather than changing several breeding variables at once.
What Should Newborn Guppies Eat?
They can usually take finely crushed quality prepared foods and small live foods such as microworms or appropriately sized newly hatched brine shrimp. Apply this within the stable water and husbandry conditions described for breeding guppies, rather than changing several breeding variables at once.
How Often Should Guppy Fry Be Fed?
Several small feedings can support growth, but frequency must be balanced with filtration and waste removal so the nursery remains stable. Apply this within the stable water and husbandry conditions described for breeding guppies, rather than changing several breeding variables at once.
How Do I Prevent Too Many Guppies?
Separate sexes when appropriate, avoid deliberately maximizing every brood, maintain realistic stocking, and arrange responsible homes before juveniles outgrow the available space. Apply this within the stable water and husbandry conditions described for breeding guppies, rather than changing several breeding variables at once.
Koi Guppy
Poecilia reticulata var. "Koi"
- Care level
- Beginner
- Adult size
- 3–6 cm
- Minimum tank
- 40 litres
- Temperature
- 17–28 °C
Lace Guppy
Poecilia reticulata var. "Lace"
- Care level
- Beginner
- Adult size
- 3–6 cm
- Minimum tank
- 40 litres
- Temperature
- 17–28 °C
Metal Guppy
Poecilia reticulata var. "Metal"
- Care level
- Beginner
- Adult size
- 3–6 cm
- Minimum tank
- 40 litres
- Temperature
- 17–28 °C