Mostly living in freshwater, guppies―popularly called millionfish or rainbow fish―belong to the Poecilia genus of the Poeciliidae family and grow to a size of about 2 inches in length. Like the other members of their family, female guppies give birth to young ones without releasing the eggs in the open. Most people choose these fish for their showy fins and vibrant colors. Guppies are tropical species; indigenous to countries like Guyana, Barbados, Trinidad and Tobago, and Antigua, as well as East Timor, Brazil, Netherlands, Vietnam, and Venezuela. Today, however, they are found all over the world, except for Antarctica. Guppy breeding can be an interesting hobby. You can selectively breed them and create a tank full of guppies of different shapes, sizes, and colors. Choosing the Right Tank Ideally, you should buy four tanks for breeding guppies: three 20-gallon tanks and one 55-gallon tank. If you want, you can buy smaller fish tanks and place some dividers in between. The basic point is, you need to have four separate areas; one each for breeding, growth of females, growth of males, and young ones. If you choose to buy all four tanks, the 55-gallon tank should be used to raise the young ones, while one of the other three tanks can be used to exclusively breed females and other males. The tank which remains can be used to keep the fish together. Breeding Guide If you are thinking of breeding guppies, you need a proper breeding setup, so as to ensure that they remain healthy and grow fast. It's important to plan how you would go ahead with the process, without which your project is more likely to go astray. Try and set some goals when you begin, like adding colorful fish later, increasing the size of the tank, etc. Your focus should only be on one aspect of breeding, i.e., if your focus is on size, you should see to it that all the fish grow to a certain size. It's only later that you should think of adding different colored fish. If you decide to let the guppies grow to a certain size, then don't suddenly introduce another guppy fish, simply because it has brilliant colors. Make sure that you don't crowd the tank, as it can stunt their growth. In a 10-gallon tank, you should not keep more than 10 guppies. If you do, there are chances that over the period, their numbers will increase to such an extent that you will have to either fish some of them or buy another tank to keep them. You should ideally change the water once every day, rather than changing it in a week. Avoid rapid changes in water quality, as it may harm these little creatures. The temperature of water should not be more than 65 to 68 ºF. While breeding, it should be increased to about 75 ºF. After their birth, guppies can be given newly hatched brine shrimp and microworms. Instead of giving them large servings once or twice a day, it's better to give them small servings at regular intervals throughout the day. In the first couple of months, feed them as much as possible, as they mature very fast and that's the time when they grow rapidly. Breeding Supplies While looking for guppies in stores, you need to ensure that you have fish of the highest quality. If you purchase the inexpensive ones, there are chances that you won't get fish of the highest order. They may serve well for first time aquarium hobbyist, but they can't supplement for high-quality ones. While buying, you should ensure that they don't come from different strains, as there are chances that they won't be able to breed well. If you are looking for guppies to breed, you should buy them from a reputed breeder. Ideally, you should purchase a couple that's young enough to live for sometime, so that you can see them grow and enjoy feeding them. Guppy breeding needs a lot of care and attention, but only in the initial stage, just after their birth. Once they mature, you don't need to spend much time caring for them. Nevertheless, make sure you feed them well or else, it might affect their health.