Breeding guide

How to breed Guppies

Beginner8 steps$40 setup

What you'll need

1 male + 2-3 female guppies
10g+ breeding tank
Floating plants (java moss, hornwort)
Optional: breeder box for pregnant females
Crushed flake + baby brine shrimp
Heater (76-78°F)

Step-by-step

Step 1: Stock with multiple females per male1M:2-3F ratio prevents male over-harassing females. Females stress out if only 1 in tank with male.

Step 2: Condition with high-protein dietFeed 2-3x daily with high-quality flake + frozen bloodworms + baby brine. Pregnant females need extra nutrition.

Step 3: Watch for pregnancy signsFemale develops dark "gravid spot" near anal fin. Belly squares off (pregnant) vs round (overfed). Pregnancy lasts 21-30 days.

Step 4: Optional: move to breeder boxFew days before due date, move pregnant female to breeder box (floating divider). Fry drop through slits + escape mom's mouth.

Step 5: Female gives birth to live fryFemale releases 10-100 live fry over 1-6 hours. Fry are fully formed mini-guppies, 0.25 inch long.

Step 6: Remove female after birthMom WILL eat fry within hours of birth. Remove her back to community OR transfer fry to separate tank.

Step 7: Feed fry crushed flake immediatelyFry eat from day 1. Crushed flake + powdered Hikari First Bites + baby brine shrimp 4-6x daily.

Step 8: Grow out 8-12 weeksSale-ready at 1 inch (8-12 weeks). Color develops at 4-6 weeks. Sex determines at 6-8 weeks.

FAQ

How often do guppies breed?

Females give birth every 21-30 days. Sustained for 12-18 months once mature. One female produces 100-500 fry over her lifespan.

Will guppies eat their babies?

YES. Both males and females eat fry within hours of birth. Either separate fry immediately or provide dense plant cover for fry hiding.

How do I sex juvenile guppies?

At 4-8 weeks: males develop gonopodium (modified anal fin), brighter colors, longer fins. Females stay round-bodied with shorter triangular anal fin.

More breeding guides

Browse all aquarium breeding guides. Pair with the Guppies care guide for full husbandry context.

Aquarium-keeping fundamentals

Whatever specific topic brought you here, four fundamentals govern long-term aquarium success: water quality, parameter stability, biological filtration, and species-appropriate husbandry. Skip any one and the others struggle to compensate.

Water quality: ammonia + nitrite at zero, nitrate under 30 ppm freshwater + 10 ppm reef. Test weekly with API or Salifert kits. Use our water parameter checker to score your readings against your tank type.

Parameter stability: stable wrong parameters beat fluctuating ideal parameters. Most fish tolerate a wide pH range if it's stable. Sudden swings of 0.4+ pH or 5+°F kill fish faster than chronic suboptimal values. Use temperature controllers (Inkbird) + automated dosing for consistency.

Biological filtration: the bacterial colony on your filter media + rock + substrate is the engine. Never replace all media at once. Use our filter turnover calculator to size correctly.

Species-appropriate husbandry: research adult size, territoriality, diet, and tankmate compatibility before purchase. Use our tank stocking calculator + compatibility guides.

Frequently asked questions

How long does an aquarium take to set up? 4-6 weeks for full cycling + first stocking. Use our cycle ETA calculator + how long does cycling take.

What's the best aquarium for beginners? 20-gallon long. Big enough for parameter stability, small enough for budget + space. See beginner picks.

How often should I do water changes? 25-30% weekly. See water change frequency Q&A + water change calculator.

Why does my fish keep dying? 5 leading causes: uncycled tank, wrong species pairings, no quarantine, undersized tank, neglected water-change schedule. See full diagnosis.