Blue Neon Female Guppy (Poecilia reticulata)

Decide whether this guppy suits you

The Blue Neon Female Guppy (Poecilia reticulata) is a peaceful poeciliid livebearer from Venezuela, Barbados, Trinidad, northern Brazil and the Guianas. This female form reaches 5 cm standard length and suits a prepared beginner who can provide a mature, filtered aquarium, mineral-bearing water and an appropriate social group. FishBase describes the species in freshwater and brackish habitats, including small streams, densely vegetated lakes and springs, ponds, canals and ditches.

Blue Neon is a selected aquarium colour label rather than a separate species or wild locality. The fish remains Poecilia reticulata, and its blue colour does not change the need for stable water, social planning or protection from fin-nipping companions. Our complete Guppy Care Guide rates guppies as easy for a prepared keeper, not as fish for an uncycled bowl or an aquarium chosen through a fish-per-litre formula.

Plan around adult size and space

Plan for a female reaching 5 cm standard length. Standard length measures the body without the tail fin, so visible tip-to-tip length may be greater. Domestic tail length varies, so a long tail adds to the overall length without changing that body measurement. Use 5 cm throughout aquarium planning rather than treating the dispatch measurement as a permanent size.

Our conservative house screen is a mature, filtered aquarium at least 60 cm long for one small guppy group, with five or more fish where the sex plan, filtration, water tests and other livestock allow. Seriously Fish gives a 45 × 30 cm base and approximately 41 litres, while FishBase gives a minimum aquarium length of 60 cm, so meet the 60 cm length even when a shorter aquarium holds 41 litres. Length, footprint and mature filtration therefore matter alongside nominal volume.

Keep the water at 22–28°C, pH 7.0–8.0 and 8–18 dGH. These routine values are the overlap of the Tropical Fish Co species guide and the Seriously Fish profile; OATA’s guppy-and-molly guidance also gives pH 7.0–8.0 and 8–18 dGH. Hold ammonia and nitrite at 0 mg/l.

Use the numbers together

• Adult size: plan around 5 cm standard length.
• Aquarium: use at least 60 cm of length under our house screen.
• Social group: plan for five or more where capacity and the sex plan allow.
• Water: maintain 22–28°C, pH 7.0–8.0 and 8–18 dGH.

Understand the female offer

One purchase supplies one Blue Neon Female Guppy at a 3–4 cm dispatch size. This measurement describes the fish sent, not its adult length, so assess the aquarium against the 5 cm adult female size. The fish is sold individually rather than as a pair, trio or complete social group.

Sex is guaranteed only when the exact product or selected option explicitly states male or female. This Blue Neon Female Guppy listing is sold as female.

A mature male guppy has a narrow modified anal fin called a gonopodium, while a mature female has a broader, triangular anal fin. Domestic females can show strong colour in the tail, so colour alone is not a reliable sexing method. Plan for the possibility that this female has already mated and may later produce fry.

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.

The pictured fish has a pale silver-gold flank and broad iridescent blue fins, but use Blue Neon as a colour direction rather than an exact pattern promise. Compare other guppy identities and stated sexes through the guppy collection, then plan every addition around the final group, filtration and adult space.

Prepare a mature aquarium before the fish arrives

Use a mature, filtered aquarium at least 60 cm long, with enough unobstructed swimming room for the complete guppy group. Larger aquariums provide more stable temperature and water quality, but litres alone do not determine a safe population. Consider the internal footprint, adult fish, sex mix, existing livestock, biological filtration and test results together.

Prepare the aquarium before adding livestock. The first tropical aquarium guide explains how to establish the system before fish arrive. Clear water is not a cycling test: confirm 0 mg/l ammonia and 0 mg/l nitrite, then add fish slowly so the biological filter can adjust to increased feeding and waste.

Arrange cover and swimming room

Provide plants or suitable ornaments for cover while retaining open water for normal movement. OATA advises gravel or sand and ideally live plants for cover; when live plants are not used, add safe artificial plants and suitable ornaments for shelter. Avoid rough or sharp furnishings that could damage fins.

Seriously Fish notes that floating vegetation is appreciated and strong currents should be avoided. Set the filter outlet so the fish can swim and feed without being continually pushed across the aquarium. Observe the result rather than judging flow only from the filter setting.

Support the biological filter and stable water quality

A working biological filter is essential. The RSPCA explains that fish release toxic ammonia and that filter bacteria convert it first to nitrite, which is also toxic, and then to the safer nitrate. Test the aquarium instead of relying on water clarity or elapsed time.

Keep ammonia and nitrite at 0 mg/l. OATA advises that nitrate should not exceed 20 mg/l above the normal tap-water level. Test at least weekly and repeat a test promptly when behaviour, breathing, feeding or appearance changes. A result above zero for ammonia or nitrite calls for immediate attention to stocking, feeding, decaying material and filter performance.

Use a consistent maintenance routine

OATA’s guppy-and-molly sheet strongly recommends, at least once a week, a 25% partial water change. Treat replacement tap water with conditioner before adding it, and keep its temperature close to the aquarium so maintenance does not create a sudden change.

Check the filter for blockages during maintenance. If reusable media needs cleaning, rinse it lightly in aquarium water removed during the partial change. Do not rinse it under the tap, because chlorine or chloramine may kill the beneficial bacterial population.

Respond to a failed test

1. Confirm the result with the test instructions followed accurately.
2. Check the filter is operating and that its media has not been replaced or damaged.
3. Look for uneaten food or other decaying material.
4. Reduce further waste input while restoring safe water.
5. Continue testing until ammonia and nitrite remain at 0 mg/l.

Keep water within the routine range

Maintain 22–28°C, pH 7.0–8.0 and 8–18 dGH. This is the overlap between the Tropical Fish Co Guppy Care Guide and the Seriously Fish species profile; OATA’s group guidance matches the pH and general-hardness range and also gives 5–15 dKH. Use stable values inside the range rather than repeatedly adjusting the aquarium towards a particular decimal.

Test the actual source water and aquarium. The aquarium water chemistry guide explains what the principal readings mean, while the water matcher helps compare measured temperature, pH and hardness with the stated range.

Choose a temperature for the whole community

Set the aquarium within 22–28°C only after checking that every resident shares that range. Use a thermostatically controlled aquarium heater when the room cannot maintain the chosen temperature, and check the water itself with an independent thermometer rather than relying solely on the heater dial.

Protect mineral stability

Seriously Fish describes the guppy as a hard-water fish whose long-term maintenance should be in moderately hard or harder water. Do not treat survival in soft or acidic water as proof that the conditions are suitable. Measure pH, general hardness and carbonate hardness before deciding whether adjustment is necessary.

Condition new tap water before it enters the aquarium. Avoid abrupt changes and do not add salt simply because the species also occurs in brackish environments. Any mineral or salt addition needs a measured purpose and a compatibility check for every animal and plant sharing the system.

Feed a complete omnivore diet in measured portions

Use an appropriately sized, nutritionally complete omnivore flake or granule as the staple. FishBase describes wild guppies feeding on zooplankton, small insects and detritus, while Seriously Fish notes that aquarium strains accept most foods offered. A complete prepared food gives a repeatable daily ration, with suitable algal and invertebrate variety supporting the broader omnivorous diet.

OATA’s guppy-and-molly guidance says guppies should only be fed what they can eat within a few minutes, once a day. Match each piece to the fish’s mouth and distribute it so every member of the group can feed. Remove leftovers before they decay, because uneaten food breaks down and releases toxic waste into the water.

Add suitable variety

Guppies will also benefit from small live or frozen foods such as daphnia, small bloodworm or tubifex. Use safe aquarium foods rather than collecting food from uncontrolled outdoor water. Variety should complement the complete staple rather than replace it with one rich treat.

Watch individuals during feeding. Repeatedly missing food, losing condition or being displaced by another fish calls for a change to food distribution, group layout or compatibility rather than simply adding a larger portion.

Manage the social group and female sex plan

Keep five or more guppies where aquarium capacity and the sex plan allow. FishBase gives an aquarium group of five or more, while OATA suggests at least three guppies or mollies. Tropical Fish Co uses the more conservative five-or-more policy because this gives a clear starting screen without turning the number into automatic permission to stock a particular aquarium.

Plan the whole group before adding this individually sold female. OATA suggests two females for each male in a mixed-sex group to reduce stress on females and other inhabitants. That ratio does not replace space, cover or observation, and more fish should not be added when filtration or usable room is already limited.

Read behaviour in context

A settled fish should swim steadily, breathe regularly, hold intact fins open and show consistent interest in food. Watch whether every guppy can reach food and move away from unwanted attention. Persistent pursuit, hiding, missed feeding or fin damage means the group or layout needs intervention.

A female-only group prevents new mating within that group, but a female may have encountered a male previously. Seriously Fish explains that females can retain viable sperm and later produce young even when no male is present. Plan spare capacity and responsible rehoming before treating a female group as certain to remain the same size.

Check the fish and aquarium every week

Combine daily observation with a written weekly maintenance check. OATA strongly recommends a 25% partial water change at least once every week, and advises testing the water at least once a week and checking the filter for blockages. Regular checks reveal gradual changes before they become visible emergencies.

Daily observations

• Look for controlled swimming and regular breathing.
• Check that the fins remain open and undamaged.
• Confirm the fish responds to food and is not excluded.
• Notice a darker or paler appearance compared with its settled norm.
• Watch for increased hiding, surface hanging or sitting on the bottom.

Weekly aquarium checks

• Test ammonia and nitrite and keep both at 0 mg/l.
• Track nitrate against the source-water reading.
• Confirm temperature, pH and hardness remain stable.
• Change 25% of the water and condition replacement tap water.
• Remove solid waste and uneaten food.
• Inspect the filter without destroying established bacteria.

Use results together. A fish hanging at the surface may be showing a water-quality or breathing problem, while reduced feeding can accompany environmental, social or health changes. Test first, inspect recent maintenance and observe the whole group rather than choosing a treatment from one sign.

After every addition, pay particular attention to feeding access, pursuit, fins and water tests. Added feeding and waste require the biological filter to increase its capacity, so a previously stable aquarium still needs monitoring after its population changes.

Follow the arrival and acclimatisation sequence

Prepare and test the mature aquarium before the delivery. Keep someone at the address to receive the parcel because live fish must not be left unattended. The delivery and Live Arrival Guarantee policy contains the full receiving conditions.

1. Receive the sealed parcel and start filming before it is opened. Keep the outer box visible and record one continuous take.
2. Open the parcel while filming. Show the fish inside the sealed bag before anything is disturbed.
3. Inspect the sealed bag. Check the fish’s condition the same day the parcel arrives.
4. Float the bag. Float the bag in the aquarium for 20–30 minutes before releasing the fish.
5. Report an arrival problem promptly. Contact us the same day with the order number and continuous unboxing video.

The fish is hand-bagged in pure oxygen and placed in an insulated poly box, with a heat pack when the weather calls for it. A licensed live-animal courier carries the parcel, and tracking plus the confirmed delivery date are sent by email so someone can receive it.

Check the aquarium separately

Before release, confirm the aquarium remains within 22–28°C, pH 7.0–8.0 and 8–18 dGH, with 0 mg/l ammonia and nitrite. Complete these tests before the delivery day so the fish can be released once the bag has floated. Continue observing swimming, breathing and balance after release, and test the aquarium if behaviour changes.

Respond to health changes with tests and observation

Act when a guppy develops persistent surface hanging, bottom sitting, erratic swimming, unusual hiding, changed breathing, appetite loss, white spots, fluffy growths, damaged fins, missing scales, ulcers or an unexplained change in body condition. These signs identify a need for investigation rather than a particular diagnosis.

The RSPCA’s fish health guidance supports checking water quality and seeking veterinary help when a fish is unwell. Test ammonia, nitrite, nitrate, pH and temperature immediately. Inspect the filter and review recent additions, maintenance, food and social behaviour.

Use quarantine to protect an established aquarium

A separate, biologically supported quarantine system allows observation without exposing established livestock. The MSD Veterinary Manual recommends at least 30 days of quarantine, with longer isolation where indicated. The quarantine aquarium still needs stable temperature, filtration, testing and suitable cover.

Do not choose salt, heat or medication solely from one outward sign. Treatments can affect fish, invertebrates and biological filtration, and different problems can produce similar behaviour. Obtain a diagnosis and follow lawful product directions or veterinary instructions.

Know when specialist help is needed

Seek prompt help when the fish is deteriorating, cannot swim normally, struggles to breathe, develops wounds or fails to improve after environmental problems are corrected. OATA maintains a UK fish-vet directory for qualified diagnosis and treatment.

Screen every tank mate before mixing

Choose companions only after checking overlapping temperature, pH and hardness, adult size, fin behaviour, territorial behaviour, feeding competition and the space needed by both social groups. No community label makes a pairing automatic, so assess the exact species and keep a practical separation plan.

Seriously Fish describes Poecilia reticulata as very peaceful and places it in quiet community aquariums with other livebearers, rasboras, corydoras, small loricariids and tetras. Those categories still contain animals with different water and group requirements. Use them as candidates for screening, not universal companions.

Avoid fin-nipping species

Do not keep this guppy with tiger barbs, serpae tetras or other species that may nip its fins. Both Seriously Fish and OATA warn against fin-nipping companions. Put that exclusion ahead of a general community reputation because persistent nipping can cause injury and continual stress.

Treat uncertain combinations cautiously

A betta and guppy combination is not a sensible default because display, territorial and long-fin interactions vary between individuals. Small shrimp or young may be eaten, while “adult invertebrates” is too broad a category for a general promise. Screen the exact animal’s water needs, adult dimensions and vulnerability.

Plan for courtship, stored sperm and fry

Include reproduction in every compatibility decision. Guppies are livebearers, and males may pursue females persistently. In mixed-sex groups, OATA suggests two females to each male, but the ratio still needs enough space, cover, filtration and feeding access for the individuals involved.

This female may later produce fry after earlier contact with a male. Seriously Fish describes long-term viable sperm retention in females, so removing males from the destination aquarium does not make possible fry irrelevant. Decide before purchase how additional fish would be housed or responsibly rehomed.

Use behaviour as the final test

• Intervene if one fish is repeatedly pursued or cornered.
• Check that every individual reaches food without continual displacement.
• Look for hiding, fin damage or declining body condition.
• Do not add more fish when filtration or swimming room is already limited.
• Keep a mature separation option for persistent conflict.

Dense planting can provide cover and improve the chance that fry survive, but survival also increases the future population and biological load. Plants therefore support a planned setup; they do not replace decisions about capacity and rehoming.

Keep Endler’s livebearer separate when preserving a documented line matters. The formal description of Poecilia wingei and Eschmeyer’s current entry treat it as a distinct species. Laboratory research confirms that P. reticulata and P. wingei can hybridise, so never represent hybrid descendants as pure examples of either species.

Answer common guppy questions

How big does a Blue Neon Female Guppy get?

A Blue Neon Female Guppy reaches 5 cm standard length, measured without the tail fin. Plan adult space around that size rather than the smaller size supplied.

What size aquarium does a Blue Neon Female Guppy need?

Use a mature, filtered aquarium at least 60 cm long under the Tropical Fish Co house screen. Seriously Fish gives a 45 × 30 cm base and approximately 41 litres, but length, footprint, group size and filtration must be considered together.

How many guppies should I keep with a Blue Neon Female Guppy?

Plan for five or more guppies where aquarium capacity and the sex plan allow. FishBase gives a group of five or more, while OATA advises at least three.

Does a Blue Neon Female Guppy suit beginners?

It suits a prepared beginner who can provide a mature filtered aquarium, 0 mg/l ammonia and nitrite, stable mineral-bearing water, a planned social group and regular maintenance.

What does this fish eat?

Feed a complete omnivore flake or granule sized for its mouth, with suitable algal and invertebrate variety. OATA advises feeding once daily and only what the fish can eat within a few minutes.

What temperature and pH does it need?

The Tropical Fish Co care guide and Seriously Fish overlap at 22–28°C, pH 7.0–8.0 and 8–18 dGH. Keep ammonia and nitrite at 0 mg/l and avoid sudden changes.

Is this fish aggressive or likely to nip fins?

Seriously Fish describes it as very peaceful. Protect its fins by avoiding tiger barbs, serpae tetras and other fin-nipping species, and continue watching feeding access and pursuit within the guppy group.

Which animals can it live with?

Seriously Fish names other livebearers, rasboras, corydoras, small loricariids and tetras for a quiet community, but each exact species must share the water range and pass adult-size, behaviour, space and feeding checks.

How does the Blue Neon Female Guppy arrive alive in the UK?

The Tropical Fish Co policy uses pure oxygen, an insulated poly box, a weather-dependent heat pack and a licensed live-animal courier. Receive the parcel in person, film continuously from the sealed box, then float the bag for 20–30 minutes before releasing the fish.

Consult the public references

• FishBase: Poecilia reticulata identity, family, native distribution, environmental occurrence, wild diet, female length and aquarium group guidance.
• Seriously Fish: species-level aquarium dimensions, water range, diet, behaviour, compatibility and sexual dimorphism.
• OATA: UK group guidance for guppies and mollies covering water, social planning, feeding, maintenance and fin-nipping risk.
• RSPCA: aquarium filtration, fish health and welfare guidance.
• Eschmeyer’s Catalog of Fishes: accepted scientific identities for Poecilia reticulata and Poecilia wingei.
• MSD Veterinary Manual: aquarium-fish quarantine and water-quality-led investigation.
• Poeser, Kempkes and Isbrücker: formal description of Poecilia wingei as a distinct species.