Poecilia reticulata female german yellow

Choose this female guppy for a prepared community

The Female German yellow guppy (Poecilia reticulata) is a peaceful, livebearing freshwater fish in the Poeciliidae family. The species is native to Venezuela, Barbados, Trinidad, northern Brazil and the Guianas, and this female colour form should be planned around an adult size of 6 cm. It can suit a prepared beginner who has a mature, filtered aquarium, tested mineral-bearing water and a deliberate social and population plan.

FishBase describes the species in warm springs, weedy ditches, canals, small streams and densely vegetated lakes and springs. That varied natural history helps explain why guppies use open swimming room as well as plant cover. It does not make an uncycled bowl, unstable water or a fish-per-litre formula suitable.

German yellow is an aquarium colour-form name, not a separate species. The accepted scientific identity remains Poecilia reticulata. Domestic females can carry strong colour, so colour alone should not be used to judge sex, pregnancy, health or the likely appearance of offspring.

This is a peaceful community fish rather than a solitary display animal. Its small body does not remove the need for swimming length, social space, mature biological filtration or a plan for possible fry. Choose it when you can maintain stable water, watch every fish at feeding time and separate individuals safely if persistent pursuit or illness develops.

Understand the female offer and gallery

One purchase supplies one fish. Build the intended group by planning the aquarium, sex mix, existing livestock and likely population before deciding how many individual fish to purchase. A single purchased fish is not a complete social group: Tropical Fish Co uses a conservative policy of five or more guppies where aquarium capacity and the sex plan allow.

Sex is guaranteed only when the exact product or selected option explicitly states male or female. This Poecilia reticulata female german yellow listing is sold as female.

A female-only purchase prevents new mating with a male in that aquarium, but it cannot rule out later fry. Female guppies may retain viable sperm after an earlier encounter with a male. Prepare capacity, filtration and a responsible rehoming plan rather than treating a female group as a certain way to prevent every brood.

The gallery images are representative of this type of animal rather than photographs of the exact animal supplied, so colours can look slightly different from the live animal.

Use the German yellow description as the colour-form identity while allowing for natural variation between individual fish. A photograph showing a rounded abdomen is not proof of pregnancy, and visible colour does not replace examination of anal-fin shape when sexing mature guppies outside a guaranteed offer.

If you are comparing colour forms or building a planned group, browse the guppy collection and assess each fish by its stated sex, adult needs and purchase unit.

Plan the aquarium around the adult group

Use a mature, filtered aquarium at least 60 cm long and plan for five or more guppies where the sex mix, filtration, water tests and other livestock allow. OATA's guppy-and-molly guidance recommends at least 45 litres for a small group of the smaller livebearers and at least three companions. Those group-level figures are not a species-specific optimum. FishBase records a 60 cm minimum aquarium length and five or more fish, so Tropical Fish Co applies the more conservative length and group screen.

Keep the aquarium at 22–28°C, pH 7.0–8.0 and 9–18 dGH. This routine plan sits within the ranges described by FishBase, Seriously Fish and OATA. Maintain ammonia and nitrite at zero mg/L, and do not let nitrate exceed 20 mg/L above the level in the tap water used for the aquarium.

Read the complete guppy care guide when planning a new group, mixed sexes or a response to unexpected fry. The decisive test is whether the mature aquarium can support the whole adult group without unstable water, missed feeding, persistent pursuit or fin damage.

Stabilise and test the water before adding fish

Keep the water at 22–28°C, pH 7.0–8.0 and 9–18 dGH. The temperature is Tropical Fish Co's routine guppy range, while the pH and hardness plan lies within the overlap of FishBase, Seriously Fish and OATA values. Use a thermostatically controlled aquarium heater whenever the room cannot keep the water in range, and confirm the water temperature with an independent aquarium thermometer rather than relying on the heater dial.

Start with zero mg/L ammonia and zero mg/L nitrite. OATA also advises that nitrate should not exceed 20 mg/L above the normal level in the tap water used for the aquarium. Test the source water as well as the tank because tap-water chemistry varies by area and can change. Our water chemistry guide explains what each test measures, while the water matcher helps compare measured values with this routine range.

A mature biological filter is essential. The RSPCA explains how filter bacteria process toxic ammonia into nitrite and then nitrate. Maturity is demonstrated by repeated water tests and stable processing of waste, not simply by leaving a filled aquarium for a set number of days.

Condition replacement tap water to remove chlorine or chloramine before it enters the aquarium. Match changes gradually and do not add salt merely because the species can occur in brackish habitats. Salt or minerals need a measured purpose and a compatibility check for every fish, invertebrate and plant sharing the system.

For a new setup, follow the steps to prepare and mature a first tropical aquarium before livestock arrives. Adding fish slowly gives the biological filter time to respond as feeding and waste increase.

Provide swimming room, cover and manageable flow

Give the adult group an aquarium at least 60 cm long, with open horizontal swimming room and planted or artificial cover. Seriously Fish describes a species-profile baseline of a 45 × 30 cm base and approximately 41 litres, while OATA recommends at least 45 litres for a small group of smaller livebearers. Tropical Fish Co uses the longer 60 cm aquarium screen because group size, sex mix and other livestock all consume usable space.

Do not treat the litre label as a stocking allowance. A nominal 60-litre aquarium can be a candidate for a small guppy group if it is at least about 60 cm long, mature, filtered, suitably furnished and not already crowded. The same volume can be unsuitable when its shape gives little swimming length, the biological filter is weak or another social group already occupies the footprint.

Arrange the interior deliberately

• Keep open water: preserve a clear swimming route instead of filling the whole footprint with dense decoration.
• Add cover: live plants, floating vegetation or suitable artificial cover let fish move out of another fish's line of sight.
• Control flow: avoid strong currents that pin, exhaust or prevent normal swimming.
• Protect small fish: ensure the filter intake cannot trap guppies or any fry that appear.
• Use a secure cover: maintain the aquarium safely while preserving the required air space around equipment.

More cover is not automatically better. Dense plants can improve refuge but may also increase fry survival and hide continuing pursuit. Watch whether every fish can use the open water, reach food and leave a contested area. Rearrange the aquarium or use the prepared separation system if one fish remains trapped, excluded or repeatedly chased.

Never choose a smaller temporary home because the fish has not reached adult size. Plan the permanent aquarium around the adult group from the start.

Feed a complete omnivore staple in controlled portions

Use an appropriately sized, nutritionally complete omnivore flake or granule as the staple. FishBase records wild guppies eating zooplankton, small insects and detritus, while Seriously Fish describes wild fish as primarily insectivorous. In the aquarium, safe compatible invertebrate and algal variety can complement the complete staple without replacing it.

OATA's guppy-and-molly routine advises feeding once a day, offering only what the fish can eat within a few minutes. This schedule is broad guidance for the group, so adjust the portion to the actual number and condition of fish while retaining the once-daily routine. Daphnia, small bloodworm or tubifex can provide occasional live or frozen variety when appropriately sized and safely prepared.

Judge the portion by the whole group

• Distribute food where every fish can reach it rather than dropping the whole portion into one contested point.
• Watch the quieter fish as well as the first individuals to reach the food.
• Stop when the planned portion has been consumed within a few minutes.
• Remove uneaten food before it breaks down and raises the waste load.
• Reduce the amount and test the water if food repeatedly remains after feeding.

A large meal is not a substitute for reliable daily observation. Overfeeding adds organic waste, which can raise ammonia or nitrite when the filter cannot process the increased load. Feeding also provides an early health and social check: reduced interest, difficulty reaching food or sudden exclusion from the feeding area needs investigation.

If fry appear, provide food small enough for their mouths and monitor water quality especially closely. Do not rely on adult food being crushed casually into an unmeasured cloud, and do not use adult or tank-mate predation as a population-control plan.

Maintain the aquarium without harming filter bacteria

At least once every week, make a 25% partial water change. Use a siphon to remove settled waste where practical, condition replacement tap water before adding it and keep the change gradual. Test ammonia and nitrite at least weekly, with nitrate, pH and temperature included often enough to identify movement away from the established routine.

Check the filter for blockages and reduced flow. If its media needs cleaning, do not run it under the tap. Rinse it lightly in aquarium water removed during the partial change so fewer beneficial bacteria are lost. Never replace all mature filter media at the same time unless the equipment maker's safety instructions require a specific damaged part to be removed.

Use the first month to establish a baseline

During the first week, record temperature, ammonia, nitrite, feeding response, swimming and breathing each day. By the end of the first month, compare those notes with weekly test results and maintenance. A consistent baseline makes a later change in appetite, flow, behaviour or water chemistry easier to recognise.

Additions increase feeding and waste, so increase the population slowly. A tank that supported one stocking level yesterday is not automatically ready for a larger group today. Stable tests after each change are more useful than a fixed waiting period.

Plan for adult growth, social pressure and possible fry

Plan this female guppy around a maximum adult size of 6 cm standard length. Seriously Fish also records 60 mm standard length. FishBase records 5 cm standard length for females, so use the larger 6 cm figure when judging swimming room, stocking and filtration. Standard length excludes the tail fin, and domestic finnage varies.

Keep five or more guppies where aquarium capacity and the sex plan allow. FishBase's aquarium note says five or more, and Tropical Fish Co uses that as its conservative house policy. OATA suggests at least three and, for mixed groups, two females to each male. A ratio can reduce pressure in some plans, but it does not guarantee that courtship, chasing or reproduction will remain manageable.

Guppies are livebearers. A female may produce young after an earlier encounter with a male, even when no male is later present. Before adding females, decide where fry could be housed, how their water would remain stable and how surplus young would be rehomed responsibly.

Do not identify pregnancy from a rounded abdomen or dark area alone. These signs can have other explanations, while exact timing and brood size vary. Watch body condition, swimming, breathing and appetite, and investigate changes rather than making a reproductive diagnosis from appearance.

Keep a mature separation option ready. It should have biologically supported filtration, suitable temperature and repeated water testing; a small uncycled container is not a safe response to chasing, illness or unexpected fry.

Respond to health changes with water tests first

A settled guppy should swim steadily, breathe regularly, hold open undamaged fins, maintain a normal body profile and feed consistently. Warning signs include hanging at the surface, sitting on the bottom, erratic swimming, unusually rapid or slow gill movement, clamped or damaged fins, spots, fluffy growths, wounds, colour change, altered aggression, persistent hiding or sudden loss of appetite.

These signs are prompts for investigation rather than diagnoses. Test ammonia, nitrite, nitrate, pH and temperature immediately. Inspect the filter, heater, recent maintenance, food, new livestock and social behaviour. Record what changed and when, using clear photographs where useful.

The RSPCA fish-health guidance supports water-quality checks and appropriate veterinary escalation. Isolate safely where that protects the affected fish or group, but use a mature, tested system rather than an unfiltered container. Do not choose salt, extra heat or medication from one symptom because different problems can look alike.

Quarantine new arrivals separately

The MSD Veterinary Manual recommends at least 30 days of quarantine, with longer isolation where indicated. Use dedicated equipment, biologically supported filtration and regular testing so quarantine does not exchange pathogens with the main aquarium or create a separate water-quality problem.

For diagnosis and treatment, use a qualified professional listed through OATA's UK fish-vet directory. Follow lawful, labelled product directions and veterinary instructions. Continue checking the whole aquarium because a visible problem in one fish may coincide with water or social conditions affecting the group.

Follow the arrival steps in order

Prepare and test the mature aquarium before the parcel is due. The Tropical Fish Co delivery and Live Arrival Guarantee policy describes oxygen-filled bags, an insulated box and a heat pack when weather conditions call for one. A licensed live-animal courier carries the parcel, and someone must be present to receive it.

1. Receive the parcel in person and do not leave live fish unattended.
2. Start a continuous video while the parcel is still sealed, with the outer box visible, before opening it.
3. Open the parcel on camera in one continuous take.
4. Show the fish still inside the sealed bag so its condition is visible before anything is disturbed.
5. Float the bag for 20–30 minutes before releasing the fish.
6. If a Live Arrival Guarantee claim is needed, report it the same day with the order number and continuous unboxing video.

Keep the video from every delivery until the fish has been inspected and released. The sealed-parcel start, continuous opening and view of the fish inside the sealed bag are part of the claim procedure, so filming cannot be reconstructed after the parcel has been opened.

After release, compare swimming, breathing, balance and fin position with the healthy baseline described above. If behaviour causes concern, test the aquarium immediately and retain the arrival video while following the reporting procedure.

Screen every tank mate before mixing

Use a quiet community plan and assess the exact species before adding it. Seriously Fish describes Poecilia reticulata as very peaceful and names other livebearers, rasboras, corydoras, small loricariids and tetras as community possibilities. These are categories to screen, not universal promises for every species or aquarium.

Check six points before mixing groups

1. Water overlap: both animals need a workable shared range, not a plan that holds either one at the edge of tolerance.
2. Adult size: assess the mature animals and whether either could swallow or injure the other.
3. Behaviour: check fin-nipping, territoriality, courtship and feeding competition.
4. Usable footprint: include the full social group required by each species rather than counting individuals in isolation.
5. Access: every animal must be able to reach food and refuge without persistent exclusion.
6. Separation: keep a mature alternative ready if observed behaviour changes.

A compatible water range is only the first screen. A nominally peaceful fish may still compete for food or space, and an aquarium may have suitable chemistry while lacking enough footprint for two social groups. Watch the actual animals at feeding time and around preferred cover.

Some platies, mollies or corydoras may pass the screen in a suitably sized aquarium. Exact species, adult needs and existing stock still matter. Introduce the new group only when ammonia and nitrite are zero mg/L, filtration is mature and the aquarium has capacity for the increased waste load.

Small shrimp or young invertebrates may be eaten, so do not treat invertebrates as automatically safe companions. “Adult invertebrates” is too broad a category for a compatibility promise; screen the exact animal for adult size, water needs and vulnerability.

Avoid fin-nippers and risky default combinations

Avoid fin-nipping species. Seriously Fish specifically says not to keep guppies with fin-nipping fish such as tiger barbs and serpae tetras, while OATA also says guppies should not be kept with species that might nip their fins. Keep these fish out of the plan rather than treating observation after mixing as the safety test.

General labels can hide important differences. The broad word “tetra” includes community candidates as well as serpae tetras, which belong under avoid. The same care is needed with livebearers and bottom-dwelling fish: each species still needs compatible hardness, pH, temperature, adult space and a suitable social group.

Monitor persistent pursuit, cornering, hiding, fin damage, missed feeding and body-condition loss. These are reasons to use the prepared separation option, not reasons to add another fish in the hope that numbers alone will solve the behaviour.

A larger or planted aquarium creates more options but cannot guarantee a risky pairing. Compatibility remains conditional on the exact animals, mature aquarium capacity and what happens after introduction.

Answer common female guppy care questions

How big does Poecilia reticulata female german yellow get?

Plan for an adult size of 6 cm standard length for this female guppy. Standard length excludes the tail, so provide adult swimming room rather than judging capacity from the fish's present length.

What size aquarium does Poecilia reticulata female german yellow need?

Use a mature, filtered aquarium at least 60 cm long. Seriously Fish describes a species-profile baseline of approximately 41 litres, OATA recommends at least 45 litres for a small livebearer group, and Tropical Fish Co applies the more conservative 60 cm length screen.

How many Poecilia reticulata female german yellow guppies should I keep?

Keep five or more where aquarium capacity and the sex plan allow. FishBase's aquarium note says five or more, and Tropical Fish Co uses the same conservative group policy; one purchased fish is not a complete group.

Does this fish suit beginners?

It can suit a prepared beginner, but it needs a mature filtered aquarium, zero mg/L ammonia and nitrite, stable mineral-bearing water, a planned social group and a response plan for chasing, illness or fry.

What does this fish eat?

Feed an appropriately sized, complete omnivore flake or granule as the staple. OATA advises one daily portion eaten within a few minutes, with suitable daphnia, small bloodworm or tubifex used as variety.

What temperature and pH does Poecilia reticulata female german yellow need?

Keep it at 22–28°C, pH 7.0–8.0 and 9–18 dGH. The Tropical Fish Co routine plan sits within FishBase, Seriously Fish and OATA ranges; maintain ammonia and nitrite at zero mg/L.

Is this fish aggressive or likely to nip fins?

It is described as very peaceful, but social pursuit and feeding competition still need monitoring. Avoid fin-nipping species, including tiger barbs and serpae tetras, because they may damage guppy fins.

Which animals can Poecilia reticulata female german yellow live with?

Other livebearers, rasboras, corydoras, small loricariids and tetras may suit a quiet community after exact water, adult-size, group-space and behaviour screening. Avoid tiger barbs, serpae tetras and other fin-nipping species.

How does this fish arrive alive in the UK?

Start filming with the parcel still sealed before opening it, then show the fish inside the sealed bag in one continuous take. Tropical Fish Co packs fish in oxygen-filled bags inside an insulated box, uses a heat pack when needed and instructs you to float the bag for 20–30 minutes before release.

Check the care references

• FishBase: Poecilia reticulata — identity, family, native range, wild habitat, diet, environmental range and aquarium notes.
• Seriously Fish: Poecilia reticulata — species aquarium dimensions, water ranges, diet, behaviour and compatibility.
• OATA: How to look after guppies and mollies — group water, feeding, maintenance, social and introduction guidance.
• RSPCA: Aquarium environment — filtration and biological waste processing.
• RSPCA: Fish health and welfare — warning signs, water checks and veterinary escalation.
• MSD Veterinary Manual: Management of aquarium fish — quarantine and water-quality-led investigation.
• OATA: Find a fish vet — UK fish-vet directory.