Things You'll Need
- Breeding aquarium
- Aquatic plants
- Aquarium salt
- Water-testing kit
- Varied fish foods
Instructions
Find a pair or several full black guppies. Although you can purchase fancy guppies in most pet stores, it's better to buy any guppies you plan to breed from an established guppy breeder. Guppy breeders can usually tell you the lineage of any guppies you buy, which means you can be sure you're getting exactly the guppies you want.
Separate the female guppies from the males for at least three months. Female guppies can hold sperm for this period of time, and use it to give birth. To ensure that your young fish are the offspring of the male guppy you've selected, you must wait for any sperm the female is holding to be used or dissipate.
Set up a freshwater breeding aquarium for the black guppies. A pair of guppies, or one male and two female guppies, can be comfortably housed in a 5-gallon aquarium. If you want to breed a larger group of guppies, you'll need a 10-gallon or larger aquarium. Breed only one pair of guppies at a time, so you know exactly which fish are breeding, and know the lineage of the young fish that are born.
Place aquatic plants, including tall plants and short, mossy plants, throughout the aquarium. These plants will shield the young fish, called fry, from the parent fish. Parent guppies often eat their young.
Add 1 tbsp. of aquarium salt to the aquarium for every ten gallons of water. Guppies, like many livebearing fish, are most comfortable in water that is brackish, or slightly salty.
Monitor the temperature of the water in the breeding aquarium. Although guppies are usually comfortable in a wide range of water temperatures, when breeding, it's best to keep the temperature of the water around 76 degrees Fahrenheit.
Measure the pH levels of the water in the breeding aquarium using a water-testing kit. Guppies are most comfortable with a pH level between 7.0 and 8.5. Use water additives to raise or lower this level if necessary.
Feed the adult guppies a nutritious diet. This should include a high-quality flake food as well as freeze-dried or live food, such as bloodworms.
Wait for the guppies to breed. This should happen almost immediately, as guppies breed frequently.
Remove the parent fish from the breeding aquarium after they've spawned. This will protect the fry from being eaten.