Freshwater Fish

The guppy (Poecilia reticulate), with its long flowing tail and spectacular colors, is probably one of the most easily recognizable fish in the aquarium hobby. And when you combine its striking appearance with its ease of care and peaceful nature, it’s easy to see why these fish are so popular.

Origin

Guppies were one of the earliest fish kept in aquariums, and they were first collected in Venezuela in 1859. When the specimens reached the British Museum of Natural History in 1861, they were given the name Girardinus guppii. Later, the name was shortened to guppy by aquarium enthusiasts, and eventually the fish came to have several names, including rainbow fish, red-tail fish, millions fish, and many others.

Characteristics
Care Level: Easy
Temperament: Peaceful
Life Span: 2 Years
Maximum Size: 2 Inches (6.5 Centimeters)
Minimum Tank Size: 5 Gallons (18 Litres)
Temperature: 65-80°F (18-27°C)

Habitat

Guppies are native to Venezuela, Brazil, Guyana, and several Caribbean islands, including Trinidad and Tobago, Barbados, Jamaica, Netherlands Antilles, and the United States Virgin Islands.

However, they have since been introduced across the globe—often in the hopes of keeping mosquito populations down—and have since become one of the most widespread fresh-water fish. Unfortunately, their introduction has had a negative impact on native species, and they’re now considered an invasive species in many countries.

Guppies can adapt to most habitats, and are found in streams, ponds, rivers, and lakes throughout their native range. Some can live in brackish water, but those are rare. Guppies prefer slow moving and shallow water and tend to avoid fast currents.

Guppy Aquarium Setup

The minimum aquarium size for guppies is 5 gallons (37 liters), but this is only if its going to be a male-only aquarium. If the tank is going to have mixed sexes, then a 10-gallon aquarium should be provided, though larger tanks are easier to maintain.

If your aquarium is going to house both males and females, then there should be a ratio of at least two females to every male. Guppy males will constantly attempt to breed with any females in their aquarium, and by having more females, it should limit the attention any one fish receives.

If there aren’t enough females to spread out the attention, then they may become stressed and ill from the constant harassment.

When setting up the aquarium, plenty of live plants should be included, along with decorations like driftwood and river stones. However, anything with sharp edges should be avoided as it can damage the guppies’ delicate tails.

It’s important to remember when setting up the aquarium, that an open swimming area should be left for the fish. As for the substrate, sand or aquarium gravel with muted colors are both excellent choices—but once again, just be sure to avoid anything jagged or sharp.

Filter

Guppies are one of the few fish where a sponge filter might be the best choice for filtration. Because of the remarkable speed of their breeding, guppy tanks are often filled with tiny fry. And while hang-on-back and canister filters will both suck the young up to their deaths, sponge filters are completely safe for the fry.

But if you don’t want to use a sponge filter, then a hang-on-back filter can still be used, but a cover should be placed over the intake (either mesh or sponge) to prevent the fry from being sucked up to their doom.

Guppy Feeding

In the wild, guppies are omnivores, though they primarily feed on algae. But they will also consume any tiny invertebrates and detritus they find while browsing for food near the bottom of the waters they inhabit.

Since nearly all the guppies for sale are captive bred, they will readily accept fish food without issue. But they should also regularly be fed lightly blanched vegetables and live or frozen foods. Some of their favorites are daphnia, blackworms, bloodworms, and brine shrimp.

Guppy Breeding

There’s an old joke among fish keepers that to breed guppies just add water. And there’s some truth to that joke. Unlike many other fish in the aquarium hobby, there are no taxing requirements to trigger breeding, and if a male and female guppy are kept together, eventually, they will produce fry.

But as previously stated, it’s important to maintain the right ratio of sexes in their tank. There should always be more females than males, and a good ratio is around 1:3, though 1:2 will still work.

To determine the sex of a guppy, simply examine their tail. The males will have long colorful tails, while the females will have short tails with muted colors.

If you want to get into more advanced identification methods, then you can look at the anal fins—the males have a narrow modified anal fin called a gonopodium—while the females have a triangular anal fin.

Another easy way to sex the females is to look for a dark area directly behind the anal fin, which is called a gravid spot.

While guppies will breed in community tanks, the survival rate of fry may be low as other fish will eat them. If you’re looking to breed guppies, then a dedicated breeding tank should be set up.

Any tank being used to breed guppies should be fully cycled, and it’s recommended to include floating plants and dense plants like Java moss. Not only does the infusoria (tiny freshwater life forms) living on the plants provide additional food sources for the fry, but the hanging roots and dense stems also act as good hiding places from hungry adult fish.

Until you’re ready to begin breeding, the males and females should be kept separately. Once you’re ready to start, then a single male and female should be placed in the tank for approximately 24 hours.

After that, the male should be removed while the female is kept alone in the breeding tank. After around 28 days, the female will give birth, at which point she should also be removed to keep the fry safe. While guppies aren’t as notorious as other fish for eating their young, new parents may still consume them.

Newborn guppies have fully developed mouths and they can eat ground up fish food immediately. However, some breeders choose to use baby brine shrimp instead or the commercially available fry food to increase the fry’s growth rate.

At around the four week mark, the male and female fry should be separated to prevent them from breeding with each other.

Guppy Tank Mates

While guppies are an excellent addition to most community tanks, they often do best in a species only aquarium. One reason for this is that their long fins often become targets for nipping, and their peaceful nature allows them to be easily bullied.

However, there are still some fish and invertebrates that coexist well with guppies. These include most corydoras catfish, kuhli loaches, bristlenose plecos, harlequin rasboras, neon tetras, otocinclus catfish, snails, and shrimp.