Poecilia reticulata female mix F1

What you are buying

Poecilia reticulata female mix F1 is our listing for female guppies in mixed colours: each purchase is one live female guppy, supplied at the size you choose. Guppies are peaceful, easy-going livebearers, but they still need a mature, filtered aquarium with moderately hard, neutral-to-alkaline water, the company of other guppies, and a plan for the fry that a female can produce even when no male is present.

The fish behind the name

The guppy, Poecilia reticulata, belongs to the livebearer family Poeciliidae. FishBase records its native range as Venezuela, Barbados, Trinidad, northern Brazil and the Guianas, and calls it one of the most popular aquarium fishes, with many standardised varieties. Despite all those colours, OATA points out that the fish sold as guppies belong to only two species: the traditional guppy, Poecilia reticulata, which is the fish on this page, and the smaller Endler’s livebearer, Poecilia wingei.

“Mix” means what it says. These females are not a single colour strain, so colour and pattern vary from fish to fish, and no particular look is promised.

What you receive

One purchase supplies one live female guppy. Sex is guaranteed only when the exact product or selected option explicitly states male or female. This Poecilia reticulata female mix F1 listing is sold as female.

Two sizes are listed, 3–4 cm and XL, and you choose between them on the product page. The size you select is the size supplied, not the adult size. XL is a grade label rather than a measured range, so ask us before you order if you need a length in centimetres. Female guppies are the larger sex: Seriously Fish gives a maximum of 60 mm standard length for the species, measured without the tail, and FishBase records 5 cm.

Both sizes are the same offer of one female, so the choice is simply the size you want to start with. Whichever you pick, set the aquarium up for adults of about 6 cm of body length, with the tail on top.

Gallery images have been digitally enhanced to improve image quality. Natural colour, pattern, size and maturity can vary between live animals.

Key facts

Three good reasons to buy females

• A female-only group: no new mating inside the tank, though stored sperm can still produce fry.
• Balancing a mixed group: OATA suggests two females to each male, so extra females take pressure off one hard-pressed fish.
• Colour in a peaceful community: mixed females add variety, provided the other fish are gentle and share the same water.

Before you order

• The aquarium is at least 60 cm long, fully cycled, and reading zero for ammonia and nitrite.
• You have tested your tap water and know how it compares with the ranges in the water section.
• You know how many guppies the tank will hold, and whether males will be part of the group.
• You have a plan for fry, including where surplus young fish would go.
• No fin-nipping species share the aquarium.

For the full background on the species, from tank sizes to Endler’s livebearers, read our complete guppy care guide.

Aquarium size, layout and flow

Guppy tank advice often starts and ends with litres, but a volume figure on its own tells you very little. The practical questions are how long the aquarium is, how mature its filter is, how many fish of each sex will share it, and what else already lives there.

What the sources say

• OATA’s guppy and molly care sheet advises buying an aquarium as large as possible within reason, with at least 45 litres for a small group of the smaller species, and more volume for every extra group.
• FishBase’s aquarium note gives a minimum aquarium size of 60 cm and groups of five or more.
• Seriously Fish lists a minimum base of 45 × 30 cm, about 41 litres.
• Our own house policy takes the more cautious reading: a mature, filtered aquarium at least 60 cm long for one small guppy group.

A larger aquarium also keeps conditions steadier. OATA notes that the larger the aquarium, the more stable temperature and water quality will be, and stability is what keeps guppies well.

Reading common tank sizes

Layout and plants

OATA recommends aquarium gravel or sand and, ideally, live plants to give cover. Where live plants aren’t used, it suggests artificial plants and suitable ornaments such as plant pots or model caves for shelter; choose pieces without sharp edges that could tear long fins. Seriously Fish adds that a planted tank with floating vegetation is appreciated. Leave clear open water for swimming as well as cover, so fish can move out of one another’s line of sight without the layout blocking normal swimming.

Flow and filter intakes

Seriously Fish advises avoiding strong currents. Aim for water movement that keeps the filter working without pinning fish against the glass, and make sure the filter intake cannot draw in small fish or fry.

Heating

In an ordinary UK home, use a thermostatically controlled aquarium heater wherever the room cannot keep the water within the range, and check it with a separate aquarium thermometer rather than trusting the heater dial. As a guide, Seriously Fish estimates roughly 50 W to hold its range in a tank of about 41 litres in a room of around 20°C.

New to setting up? Our guide to setting up and maturing a first tropical tank covers the whole process, from an empty aquarium to a filter ready for its first fish.

Water: the ranges and why hardness matters

Guppies are adaptable, but they are not soft-water fish. Seriously Fish’s guppy profile describes the guppy as a hard water fish: it may manage in soft or acidic water, but long-term it should be kept in moderately hard or harder water.

The ranges to aim for

The pH and hardness figures come from OATA’s combined guppy and molly sheet, which covers the group rather than guppies alone. Broader figures appear in the species references: FishBase gives 18–28°C, pH 7.0–8.0 and 9–19 dH for the wild environment, and Seriously Fish’s species range runs to 17–28°C, pH 7.0–8.5 and 8–30 dGH. Keeping the aquarium within the routine range, rather than at the edges of those wider figures, leaves a margin for a heater fault or a missed water change.

Salt is not part of routine care

FishBase records guppies from fresh and brackish water, and that sometimes leads keepers to add salt. Brackish records are not a reason to salt a freshwater aquarium: add no salt or minerals without a measured purpose and a check that every animal and plant in the tank can take it.

Know your tap water

UK tap water varies from region to region, and suppliers can blend or change their sources. Read your water company’s current report, then test the water you actually use for changes. Our guide to aquarium water parameters explains what each test tells you, and the water parameter matcher lets you compare your readings with the ranges above.

• Hard, alkaline tap water often suits guppies with little adjustment.
• Very soft or acidic water needs a consistent, measured way to raise hardness and pH before the fish arrive.
• Whatever the source, make every change of conditions gradually.

Filtration, cycling and weekly maintenance

The RSPCA’s aquarium environment guidance is clear that no fish should be kept without a well set up and maintained filter. Fish release ammonia, which is toxic. A working biological filter grows beneficial bacteria that convert it to nitrite, also toxic, and then to nitrate, which is safer. OATA adds that whatever the size of the aquarium, a filter is always essential.

Sizing the filter

Seriously Fish suggests a turnover of four to five times the tank volume an hour, which for a tank of about 41 litres means a filter rated at roughly 165–205 litres per hour. Balance that against its advice to avoid strong currents: the aim is good turnover without a current that pushes the fish around.

Cycling before the fish arrive

Confirm that the filter is mature with repeated water tests, not by counting weeks. Ammonia and nitrite should both read zero before the first guppy goes in, and OATA’s advice is to increase fish numbers slowly afterwards, because the bacteria must grow each time more fish are added and feeding increases. Overstocking or stocking too quickly can cause “new tank syndrome”, in which ammonia and nitrite rise to unhealthy levels and fish may become ill or die.

The weekly routine

1. Test ammonia, nitrite and nitrate at least once a week.
2. Make a partial water change of 25% at least once every week, siphoning solid waste from the gravel or sand as you go.
3. Treat the replacement water with tap water conditioner to remove chlorine or chloramine, and bring it close to the tank’s temperature.
4. Check the filter for blockages.
5. If the filter needs cleaning, rinse the media lightly in the tank water you have just removed, never under the tap, where chlorine or chloramine may kill the bacteria.

OATA stresses that good husbandry is essential because guppies can be stressed by even the smallest amounts of ammonia. A short log of each week’s readings shows a slow drift long before the fish do.

Feeding female guppies

Wild guppies are opportunists. FishBase records them feeding on zooplankton, small insects and detritus, and Seriously Fish describes wild fish as primarily insectivorous. Tank-bred guppies are far removed from their wild ancestors, though, and will accept most foods offered.

A simple feeding plan

• Staple: a good-quality flake or granule with a high algae content, which is OATA’s recommendation, in a size the fish can take easily.
• Variety: small live or frozen foods such as daphnia, small bloodworm or tubifex, which OATA says guppies benefit from.
• Portion: only what they can eat within a few minutes once a day, following OATA’s guidance.

Portion for the group you actually have

A timetable is only a starting point. Watch each meal and make sure every female is getting food, not just the boldest fish, and adjust the amount to what the whole group clears. Take care not to overfeed: uneaten food breaks down and releases toxic waste into the water. Siphon out anything left behind rather than letting it sit until the weekly change.

If fry appear

Fry need food sized for their mouths, and water that is monitored even more closely than the main tank. Before you decide to raise a brood, get welfare-focused advice for the nursery, food and filtration you plan to use, rather than copying a fixed growth timetable.

Why a female-only group can still have fry

This is easy to overlook when you buy female guppies. Guppies are livebearers that give birth to live young, and a female can go on producing young long after her last contact with a male.

Stored sperm

Seriously Fish explains that excess viable sperm can be stored in the female’s oviduct, so females may still produce young for six months or more with no male present. Our guppy guide cites peer-reviewed work documenting sperm storage over several months. The practical result is simple: a group of females can still produce fry after purchase, so plan space and responsible rehoming before you buy rather than assuming a female-only tank stays childless.

FishBase notes that females mature at about three months of age, and males at about two months.

Signs are not proof

A rounded abdomen or a dark patch behind the belly is not, on its own, proof that a female is pregnant, so plan for the possibility rather than trying to predict it. We make no promise about gestation length or brood size, because timing and numbers vary and a female may have mated before sale.

If young fish appear

• Adult fish will eat the young, but that is not a population plan or a welfare plan.
• Dense planting and floating plants help fry survive, which also means more fish to house, feed and filter.
• A nursery should be a separate, cycled system with working filtration, a suitable temperature and regular tests showing zero ammonia and nitrite. A small uncycled container, or shutting a female away in a confined space, is not a safe shortcut.
• Decide in advance where surplus fish will go, whether to a larger tank or to another keeper.

Never release guppies or tank water outdoors

Guppies have been introduced far beyond their native range. FishBase records that these introductions, mostly for mosquito control, had rare to non-existent effects on mosquitoes and negative to perhaps neutral effects on native fishes. Never release guppies, fry, plants, snails or aquarium water into a pond, drain or natural waterway, and dispose of old water and substrate where nothing living can escape.

Health, quarantine and getting help

A settled guppy swims steadily, breathes at a regular pace, holds its fins open and undamaged, keeps a normal body shape and feeds consistently. OATA describes healthy fish as having clear, bright eyes, undamaged fins, intact scales and no ulcerations or bumps.

Warning signs

• Hiding more than usual, or clamped fins.
• Gasping at the surface, or gill covers moving faster or slower than normal.
• Loss of balance, hanging at the surface or sitting on the bottom.
• White spots, fluffy growths, wounds, or loss of fins or scales.
• A sudden change in appetite or body condition.

These are warning signs, not a diagnosis, and the right first response is the same whichever you see.

What to do

1. Test ammonia, nitrite, nitrate, pH and temperature straight away.
2. Check the filter, the heater, your most recent maintenance, the food and any new arrivals, and watch how the other fish are behaving.
3. Note the signs with dates or photographs.
4. Isolate the fish safely where that is appropriate, and get qualified help through OATA’s directory of fish vets.

Don’t choose salt, extra heat or medication on the strength of one symptom. The RSPCA’s fish health guidance is a good reference for normal and concerning signs and when to involve a vet.

Quarantine for new fish

New guppies joining an established tank are safest after a spell in a separate quarantine system with its own equipment, biological filtration and regular testing. The MSD Veterinary Manual’s guidance on managing aquarium fish recommends at least 30 days, and longer where indicated. In the UK, any treatment should be a lawfully labelled product used under veterinary direction.

Delivery day and settling in

Before the order is placed, the aquarium should already be mature, tested and ready. Your guppies are hand-bagged in pure oxygen inside an insulated poly box, with a heat pack when the weather calls for it, and travel on a tracked service with a licensed live-animal courier. We email the tracking number and your confirmed delivery date, so you can plan to be in. Our delivery and Live Arrival Guarantee terms set out the full detail.

Getting ready

• Test the aquarium in the days before delivery, so you know it is stable and reading zero for ammonia and nitrite.
• Have tap water conditioner, your test kit and a thermometer to hand.
• Make space at the surface of the tank to float the bag.
• Charge your phone so you can film the unboxing from start to finish.

When the parcel arrives

1. Be at the delivery address to take the parcel in; live fish cannot be left unattended.
2. Start filming a single continuous unboxing video while the box is still sealed, and keep recording as you open it until the fish can be seen inside the sealed bag.
3. Open and inspect the parcel on the day it arrives.
4. Float the sealed bag in the aquarium for 20–30 minutes so the fish acclimatise slowly.
5. Transfer the fish into the tank and keep the bag water out of it.
6. If anything has gone wrong, contact us the same day, by WhatsApp for the quickest reply, with your order number and the video, and we will arrange a replacement or refund.

The Live Arrival Guarantee relies on three things: someone at the address to receive the parcel, the parcel opened and inspected on the day it arrives, and a continuous unboxing video that starts with the parcel still sealed.

The first days

Watch the new females closely for swimming, breathing, fins and balance. If their condition or behaviour worries you, test the aquarium and report it promptly, rather than assuming continuing distress is just the journey. Add further fish gradually, testing after each addition, so the filter’s bacteria keep pace with the extra waste.

• Check that each new female is feeding at every meal.
• If you keep males, watch for persistent chasing of the newcomers.
• Keep up the weekly routine from day one.

Groups, ratios and tank mates

Guppies are sociable fish. OATA says guppies and mollies need some companionship and suggests keeping at least three together, with two females to each male in a mixed group to reduce stress on females and other tank mates. More can be kept, provided they are added in that ratio. FishBase suggests groups of five or more, and that is also our house recommendation where space and your sex plan allow.

Choosing a group plan

Males and pressure on females

Seriously Fish advises keeping several females to each male, because males can be quite vigorous in their constant pursuit of females, and peer-reviewed work cited in our guide shows that male harassment can change where females spend their time. Give the group room, cover and places to move out of a male’s line of sight, watch feeding and body condition, and keep a cycled tank or separation option ready. Repeated chasing, cornering or hiding needs action, however peaceful guppies are as a rule.

How to tell the sexes apart

If you add fish from other sources, check the anal fin rather than the colour. A mature male has a narrow, stick-like modified anal fin called a gonopodium, while a female’s is broader and triangular. Females are larger and plumper and generally duller, though aquarium varieties can show strong colour in the tail.

Tank mates

Seriously Fish describes the guppy as a very peaceful fish that does well in a quiet community with other livebearers, rasboras, corydoras, small loricariids and tetras. The main rule is about fins: guppies should not be kept with fin-nipping species such as tiger barbs or serpae tetras, and OATA warns against any species that might nip their fins, such as barbs. Before adding any companion, check:

• that its temperature, pH and hardness needs overlap well with the guppies’, not just at the edges;
• its adult size, and whether either fish could swallow or injure the other;
• its fin-nipping, territorial and feeding-competition risk;
• that the aquarium still has space once both groups are included, and that every fish can reach food and cover.

Small shrimp may be eaten, and a betta with guppies is not a sensible default, because display, territorial and long-fin interactions vary between individuals.

Endler’s livebearers

Endler’s livebearer, Poecilia wingei, was formally described as a distinct species, and Eschmeyer’s Catalog of Fishes treats it as valid. Laboratory research confirms that the two species can hybridise, and hybrid young are neither pure guppies nor pure Endlers, so house the two species separately if you want to keep either line true. If you are building a mixed group and need males, or want to add more females, browse our guppy range and check each listing’s sex and size before you order.

Female guppy questions

How big do Poecilia reticulata female guppies grow?

Females are the larger sex. Seriously Fish gives a maximum of 60 mm standard length for the species, measured without the tail, and FishBase records 5 cm; OATA describes traditional guppies as about 5 cm. Planning for a body of about 6 cm, plus the tail, keeps you on the safe side.

What size aquarium do female guppies need?

Our house policy is a mature, filtered aquarium at least 60 cm long for one small guppy group, matching FishBase’s 60 cm minimum. OATA’s floor of 45 litres for a small group is a starting point only, because length, filtration, tank mates and water tests all matter as much as volume.

How many Poecilia reticulata females should I keep together?

FishBase suggests groups of five or more, and that is our house recommendation where space allows. OATA’s floor is at least three guppies together, and in a mixed group it suggests two females to each male.

Are female guppies a good choice for beginners?

We rate guppies as easy for a prepared beginner. That means a fully cycled aquarium with zero ammonia and nitrite before they arrive, stable water, a planned group, and a plan for any fry; they do not tolerate being added to a new, uncycled tank.

What do Poecilia reticulata guppies eat?

OATA describes guppies as omnivores that take most foods. Use a good-quality flake or granule with a high algae content as the staple, add small live or frozen foods such as daphnia or small bloodworm, and feed only what they can eat within a few minutes once a day.

What temperature and pH do Poecilia reticulata need?

Our routine range is 22–28°C. OATA’s group guidance for guppies and mollies gives pH 7.0–8.0, general hardness of 8–18°dH and carbonate hardness of 5–15°dKH, with ammonia and nitrite at zero.

Are guppies aggressive, and do they nip fins?

Seriously Fish describes the guppy as a very peaceful fish. The fin-nipping risk runs the other way: guppies should not share a tank with fin-nipping species such as tiger barbs or serpae tetras.

Which fish can live with Poecilia reticulata females?

Seriously Fish lists other livebearers, rasboras, corydoras, small loricariids and tetras as kinds that do well with guppies in a quiet community. Check each species’ own water, size and behaviour first, and remember that small shrimp may be eaten.

How do the guppies arrive alive in the UK?

Each order is hand-bagged in pure oxygen and packed in an insulated poly box, with a heat pack when the weather calls for it, then carried by a tracked, licensed live-animal courier. Someone must be in to receive it; record a continuous unboxing video from the sealed parcel, float the bag for 20–30 minutes and keep the bag water out of your aquarium.

Sources

• FishBase: Poecilia reticulata, for family, native range, recorded size, wild environment and diet, the aquarium note, maturity and introductions.
• Eschmeyer’s Catalog of Fishes: Poecilia reticulata, for the accepted name.
• Seriously Fish: Poecilia reticulata, for adult length, tank base, water tolerance, filtration, diet, behaviour, sexing and stored sperm.
• OATA: How to look after guppies and mollies, for group guidance on water, aquarium size, layout, maintenance, feeding, health signs and compatibility.
• RSPCA: fish environment and RSPCA: fish health, for filtration and health signs.
• MSD Veterinary Manual: management of aquarium fish, for quarantine.
• OATA: find a fish vet, for qualified diagnosis and treatment advice.
• Poeser, Kempkes and Isbrücker (2005): description of Poecilia wingei and Eschmeyer’s Catalog of Fishes: Poecilia wingei, for Endler’s livebearer as a separate species.
• Tropical Fish Co guppy care guide and delivery page, both linked above, for our house policies, sperm-storage research and arrival terms.