Assorted Molly (Poecilia spp.)

Assorted Molly fish are lively domestic livebearers selected from the Molly stock available at the time of dispatch. Rather than promising one named colour or fin shape, this listing offers an assorted individual: it may be orange, silver, spotted, black-gold or another colour form represented in the current group. Each quantity adds one unsexed fish. Colour, pattern, sex and exact markings cannot be chosen or guaranteed.

The supplier records this stock as a Poecilia sphenops mix, although its source sheet misspells the species as “shpenops”. Poecilia sphenops is the accepted spelling, but domestic Mollies have been selectively bred for many generations and some aquarium lines have mixed ancestry. For that reason, the most honest label for an unspecified assortment is Poecilia spp. (domestic Molly assortment), with P. sphenops retained as the supplier’s reference species rather than a promise of a genetically pure strain.

Mollies do best in a mature, mineral-rich freshwater aquarium with stable warmth, open swimming room, plant cover and good biological filtration. They are social and usually suitable for a carefully planned community, but males may pursue females and individuals can be assertive at feeding time. This is a colourful, active fish, not a passive decoration: plan the adult group, water hardness and possible fry before ordering.

What does “assorted Molly” mean?

“Assorted” describes the way the fish is selected, not a separate wild species. The available holding group can contain several colours and patterns. The image on this page shows four representative examples on one black background so customers can understand the kind of variation possible. It does not show the exact individual that will be packed, and it does not mean four fish are included.

One quantity buys one fish. We cannot promise orange, silver, Dalmatian-style spotting, black-gold markings, a particular tail shape or a male or female. Natural growth, age, lighting and stress can also change how a colour looks. A newly transported fish may be paler than a settled adult and should be judged after careful acclimation, quiet recovery and normal feeding.

If a precise appearance matters more than surprise, compare the named Molly listings rather than ordering an assortment. Our Black Molly, Gold Black Molly and Molly Lyra Mix pages are clearer starting points for a defined colour or fin preference, subject to their live stock. The wider Molly fish collection lets you compare the current range in one place.

Scientific identity and domestic ancestry

Poecilia sphenops Valenciennes, 1846 is a valid Molly species in the family Poeciliidae. FishBase records the reference species from fresh and brackish habitats from Mexico to Colombia and notes that it can be confused with related Poecilia. The aquarium trade, however, contains many domesticated colour and fin forms. Assorted commercial stock may not arrive with a documented pedigree, so presenting every fish as a pure wild-form P. sphenops would sound precise without being properly evidenced.

That uncertainty does not reduce the fish’s value; it changes the responsible description. This page uses Poecilia spp. for the assortment, explains the supplier’s P. sphenops reference and avoids attaching a specific strain name to a fish that has not been individually identified. It also avoids treating balloon, sailfin and standard-bodied Mollies as interchangeable. This listing is for the supplier’s standard assorted Molly group, not a promise of balloon or sailfin form.

The source size band is approximately 3-4 cm, but that is a dispatch-stage measurement rather than a permanent size. Standard Mollies commonly remain below about 10 cm, while some larger sailfin forms need substantially more room. Plan this stock around an adult standard-bodied Molly and monitor development rather than using the arrival measurement to justify a small tank.

Is an Assorted Molly right for your aquarium?

This fish is a good match for a keeper who has naturally medium-hard or hard tap water, a properly cycled aquarium and room for a social group. Mollies are active in daylight, feed readily and use much of the water column. Their movement and varied colours can make a planted community feel animated without relying on one centrepiece fish.

They are less suitable for very soft, acidic aquariums, new tanks or nano displays. A broad internet description of Mollies as “hardy” can be misleading: they tolerate ordinary variation once established, but they can deteriorate in immature water, chronically low hardness or unstable temperature. A fish that shimmies, clamps its fins or hangs at the surface needs a water-quality investigation, not a label of easy-care resilience.

Think about reproduction before purchase. Mollies are livebearers, and a female can give birth after arriving even when no male is currently present in your aquarium. A community may eat some fry, while dense plant cover can allow many to survive. The filter and tank volume must be able to support any fish you choose to raise, and unwanted fry should never be released outdoors.

Tank size and group planning

For a small group of standard-bodied Mollies, use an aquarium of at least about 75 litres and 75 cm in length. This is a practical starting point above the bare minimum, with enough room to create open swimming lanes and planted retreats. Choose a larger aquarium when adding other fish, keeping more than three Mollies or accommodating an unexpectedly large adult form. Volume printed on a tank is not the same as usable water after substrate and decor are added.

Keep at least three Mollies together. When sex can be identified, aim for at least two females per male so one female does not receive all of a male’s courtship attention. This assorted listing is unsexed, so an order cannot guarantee that ratio. Check the anal fin as fish mature: males develop a narrow gonopodium, while females retain a broader fan-shaped anal fin. If the resulting group is male-heavy, be prepared to add suitable females from a sexed source or separate a persistent chaser.

A group needs more than litres. Long stems, floating plants and wood can interrupt a direct pursuit without filling every swimming lane. Give subordinates more than one route away from a dominant fish. Place food in two or three areas so every fish can eat. Chasing that ends quickly can be ordinary social behaviour; a fish that is repeatedly cornered, losing weight or excluded from food needs intervention.

Substrate, plants and equipment

Sand or smooth gravel both work. Mollies are not dedicated bottom diggers, so choose substrate around plant growth and maintenance. Use robust live plants where your light and water allow them, including taller growth at the back and sides. Floating cover can make new arrivals feel secure, but leave open surface access and do not allow plants to stop gas exchange or block the filter.

Fit a heater with a guard, a correctly sized filter and a visible thermometer. The outlet should move the surface without turning the whole aquarium into a fast-flow river. Mollies appreciate oxygenated water but also need ordinary swimming and resting areas. A lid reduces jumping risk and limits sudden temperature change. Test water rather than treating clear water as proof that the aquarium is ready.

Water parameters and water quality

A useful long-term target is 22-26°C, pH 7.0-8.0 and 8-18 dGH. OATA’s Molly guidance gives 20-28°C and the same pH and general-hardness range; FishBase records a wider 18-28°C species range for P. sphenops. The narrower target on this page leaves room for normal fluctuation without deliberately holding fish at an outer tolerance limit.

Stability matters more than chasing a textbook decimal. Check your tap water before changing pH or hardness. If it is already suitable, regular conditioned water changes are usually safer than repeated chemical adjustment. If it is very soft, research a measured remineralisation plan before purchase. Do not add shells, mineral blocks or buffers blindly, because rapid changes can be more stressful than a slightly imperfect but stable reading.

Ammonia and nitrite should remain at 0 mg/l. OATA advises keeping nitrate no more than 20 mg/l above the normal tap-water level. Test at least weekly and whenever behaviour changes. Replace roughly a quarter of the water each week as a starting routine, adjusting for real test results and stocking. Treat new tap water for chlorine or chloramine and bring it close to the aquarium temperature before it enters the tank.

Measure	Working target	Action if it drifts
Temperature	22-26°C	Check heater, room heat and thermometer; change gradually
pH	7.0-8.0	Check source water and hardness before using additives
General hardness	8-18 dGH	Use a measured remineralisation approach if tap water is too soft
Ammonia	0 mg/l	Stop adding livestock, test the filter cycle and make an appropriate water change
Nitrite	0 mg/l	Treat as a cycling or filtration problem and increase monitoring
Nitrate	No more than 20 mg/l above tap baseline	Review water-change frequency, feeding, plants and stocking

Do Mollies need aquarium salt?

No universal salt dose is required for this freshwater listing. Wild Molly species can occur in waters with different salinities, and some keepers use salt for a defined husbandry or treatment purpose. That does not make routine salt the correct answer for every domestic Molly, every plant or every tank mate. Keep these fish in stable, mineral-rich freshwater unless a qualified aquatic professional has recommended a specific salinity plan for a diagnosed reason.

Salt is not a substitute for hardness, a cycled filter or clean water. It can also be inappropriate for some companion species and plants. If a fish is unwell, first measure temperature, ammonia, nitrite, nitrate, pH and hardness and seek diagnosis rather than adding an unspecified spoonful to the tank.

What should Assorted Mollies eat?

Mollies are omnivores with a meaningful plant and algae component in their diet. Use a high-quality flake or small granule formulated for community fish, ideally with spirulina or another plant-rich ingredient. Rotate that staple with small portions of suitable frozen or live food such as daphnia, cyclops, brine shrimp or finely sized bloodworm. They may graze soft algae and biofilm, but visible growth is enrichment rather than a complete ration.

Feed only what the group can finish in a few minutes, normally once or twice a day depending on fish size, stocking and food type. Scatter small amounts across the surface or use more than one feeding point. Watch each fish take food; a bold group can conceal a subordinate that is slowly losing condition. Remove accumulating leftovers and reduce portions when nitrate rises or food reaches the substrate uneaten.

Do not rely on one rich protein food. Excessive feeding pollutes water and can leave fish in poor body condition. A varied but measured menu is more useful than a long ingredient list. During the first day after delivery, keep feeding light or wait until the fish is settled and breathing normally.

Food	Purpose	Use
Plant-rich flake or small granule	Everyday balanced staple	Small measured portions that all fish can reach
Daphnia, cyclops or brine shrimp	Protein and behavioural variety	Modest portions several times per week
Soft algae and biofilm	Natural grazing	Useful enrichment, never the only food
Blanched courgette or spinach	Occasional plant supplement	Offer a small clean piece and remove leftovers

Temperament, sex ratio and behaviour

Mollies are usually described as peaceful community fish, but that phrase needs context. They are confident, busy livebearers and can be forceful around food. Males court frequently, and persistent pursuit can exhaust a female that has nowhere to move away. Similar-looking males may display or chase one another. Adequate room, visual cover and the right sex ratio make the “peaceful” description much more likely to match what the keeper sees.

Normal fish should explore, hold fins open, breathe steadily and show interest in food. Short displays and brief chases can occur. Warning signs include one fish being kept behind a filter, repeated surface gasping, clamped fins, shimmying, pale colour, a sunken abdomen or refusal to eat. Test water immediately when behaviour changes; do not assume every symptom is infectious disease.

The fish are sold unsexed. Young Mollies may be difficult to identify confidently, and pregnancy is not guaranteed or excluded. A customer who needs a controlled breeding trio should buy from a source offering individually sexed fish rather than expecting an assorted order to produce the desired ratio.

Tank mates and compatibility

Choose companions that share warm, alkaline, medium-hard to hard water and are not large enough to eat a Molly. Platies and selected swordtails often occupy similar water conditions, while other community fish must be checked species by species. The livebearer and Molly category is useful for comparison, but appearing in the same category does not automatically make two fish compatible.

Avoid persistent fin nippers, aggressive cichlids, predatory fish and very timid species that will lose every feeding contest. Long-finned companions can attract attention from an inquisitive group. Very soft-water specialists are a poor compromise even when they look peaceful. Also compare adult size and group requirements: a tank can have correct chemistry and still be too crowded.

Other Mollies can live together when the aquarium has room, but adding more males can increase pursuit. Mixing varieties also means any fry will not preserve a named strain. If a breeding project requires predictable colour or finnage, house a documented line separately and do not mix the assortment into it.

Companion type	Assessment	Main question
Platies and suitable swordtails	Often compatible	Is the aquarium large enough for both adult groups?
Other standard Mollies	Usually possible	Will the final sex ratio increase chasing?
Peaceful hard-water community fish	Case by case	Do temperature, hardness, size and feeding style all overlap?
Fin nippers or aggressive fish	Avoid	Could they injure or repeatedly intimidate a Molly?
Very soft-water specialists	Poor match	Would either species be kept outside its proper chemistry?
Fish large enough to swallow a Molly	Avoid	Compare adult mouth size, not current juvenile size

Breeding, pregnancy and fry

Mollies are livebearers: embryos develop inside the female and free-swimming young are born rather than eggs being laid in the aquarium. A mature female can produce fry after arrival, and previous contact with males can matter even if no male is currently visible. Gestation and brood size vary with age, temperature, condition and lineage, so this listing does not promise a breeding date or number.

Dense fine-leaved or floating plants give fry places to avoid adult fish. A separate mature rearing aquarium offers more control, but it also requires filtration, stable heat and frequent small feeds. Breeding boxes should not be used as long-term cramped housing for an adult female. Move or confine fish only when you understand the stress and water-quality consequences.

Before encouraging fry, decide where adult offspring will live. A few births can quickly exceed the capacity of a small aquarium. Never release aquarium fish or water containing organisms into a pond, stream or drain connected to natural water.

Health checks and common warning signs

A healthy Molly normally has clear eyes, intact scales, open fins, steady respiration and controlled swimming. It should be curious without continuously racing the glass. The body should look filled out rather than pinched behind the head. After transport, temporary hiding or subdued colour can occur, but breathing should settle as temperature and water chemistry are matched.

Shimmying or rocking in place is a sign to investigate, not a disease name. Check for ammonia, nitrite, unsuitable hardness, low temperature, rapid parameter change and bullying. White spots, fluffy growth, ulcers, persistent rubbing or damaged fins require closer diagnosis and isolation where appropriate. Avoid adding medication to the display without identifying the likely problem and checking safety for every species present.

Quarantine new fish when you have a suitable mature system. Separate nets and siphons reduce cross-contamination. During routine maintenance, rinse filter media gently in removed aquarium water rather than chlorinated tap water, and do not replace all biological media at once. Stable husbandry prevents more problems than reactive treatment.

Delivery, acclimation and the first week

Prepare the aquarium before ordering: the filter must be cycled, water should be within range and all intended tank mates must be compatible. The current dispatch arrangement and live-stock terms are explained on our live fish delivery page. Keep somebody available to receive the parcel on the confirmed day and inspect the sealed bag promptly.

Turn off the aquarium light before opening the outer packaging. Equalise temperature, then introduce small amounts of aquarium water gradually so the fish is not exposed to an abrupt chemistry change. Do not pour transport water into the aquarium. The exact pace should reflect the difference between bag and tank water rather than a rigid timer, but our acclimation timer provides a practical guided sequence.

Release the fish into a calm tank with several hiding routes. Keep lighting low for the rest of the day and feed lightly only after normal posture and breathing return. For the first week, observe appetite, fins, respiration, faeces and social pressure. Test water after adding livestock because the biological load has changed.

Eligible livestock is covered by our Live Arrival Guarantee when the published receiving, evidence and contact conditions are followed. Read the current guarantee and returns conditions before dispatch, including what to record if a fish arrives in difficulty. Those pages, checkout and your order confirmation are the live source of truth for delivery promises.

What to check before ordering

1. Confirm at least 75 litres and appropriate length for the planned adult group.
2. Test ammonia and nitrite at zero, plus pH and general hardness.
3. Make sure the aquarium is mature, heated, filtered and covered.
4. Plan for at least three Mollies and a workable sex ratio once they mature.
5. Accept that each quantity is one unsexed, randomly selected colour form.
6. Check every tank mate against adult size, water chemistry and temperament.
7. Prepare for possible fry even if you are not planning to breed.
8. Review current delivery and Live Arrival Guarantee requirements.

Eligible first-time customers can use WELCOME10 for 10% off their first order. The code is applied at checkout and cannot change the care, group or tank-size requirements. Current stock, price, discount eligibility and final order total are always confirmed by the live selector and checkout rather than fixed text in this description.

Assorted Molly questions

How big do Assorted Molly fish get?

Plan for roughly 8-10 cm for a standard-bodied adult Molly. The supplier’s approximate 3-4 cm source size is a juvenile dispatch band, not the permanent size. Larger Molly forms need more room, but this listing does not promise a sailfin variety.

How many Mollies should be kept together?

Keep at least three. When sexes are known, aim for at least two females per male to spread courtship pressure. This assortment is sold unsexed, so be ready to adjust the group if it matures with an unsuitable ratio.

What colour Assorted Molly will I receive?

One fish is selected from the colours available at dispatch. Orange, silver, spotted, black-gold and other domestic forms may occur, but no colour, marking, sex or tail shape can be guaranteed.

Does the picture mean I receive four Mollies?

No. The image is a representative composition showing several possible appearances. Each quantity adds one unsexed fish to the order.

Are these definitely pure Poecilia sphenops?

No pure-strain guarantee is made. The supplier calls the stock a P. sphenops mix, but domestic assorted Mollies can have uncertain or mixed aquarium ancestry. The conservative customer label is Poecilia spp.

What tank size do Assorted Mollies need?

Use at least about 75 litres and 75 cm of length for a small group of standard-bodied Mollies, then increase space for more fish, larger adults or a mixed community. A mature filter and usable swimming room matter as much as the headline volume.

What temperature is best for Molly fish?

A practical long-term target is 22-26°C. Published care ranges are broader, but holding fish away from the extremes gives more room for ordinary fluctuation. Match every companion to the same stable range.

What pH and hardness do Mollies need?

Aim for pH 7.0-8.0 and 8-18 dGH. Test the actual tap and aquarium water. Stable medium-hard or hard freshwater is preferable to frequent chemical changes made only to hit an exact number.

Do Mollies need salt in freshwater?

Routine salt is not mandatory for this listing. Keep the fish in stable, mineral-rich freshwater and use salt only for a clearly defined purpose that is safe for every aquarium resident and supported by appropriate professional advice.

What should I feed an Assorted Molly?

Use quality flake or small granules with a good plant or algae component, supported by small portions of suitable frozen or live foods. Natural grazing is useful enrichment but not a complete diet.

Are Mollies peaceful community fish?

They are generally community-compatible, but they are active and males can chase females persistently. Provide space, cover, multiple feeding points and a suitable sex ratio, and avoid aggressive fish, fin nippers and very timid competitors.

Can a female Molly arrive pregnant?

Yes, it is possible because Mollies are livebearers and previous contact with a male can result in later fry. Pregnancy is neither guaranteed nor excluded, so every keeper should have a population plan.

How long do Mollies live?

They can live for several years in a mature aquarium with appropriate water, diet and social care. Lifespan varies with lineage, prior history and husbandry, so an exact number cannot be promised for an assorted individual.

Can I request a male, female or specific colour?

No. This listing is intentionally assorted and unsexed. Choose a separately listed, individually identified fish if a specific breeding ratio or appearance is essential.

Does WELCOME10 and the Live Arrival Guarantee apply?

Eligible new customers can use WELCOME10 for 10% off their first order. Eligible livestock orders are covered by the Live Arrival Guarantee when the current receiving, evidence and contact conditions are followed; check the delivery and returns pages before ordering.

Evidence and further reading

This page separates the supplier’s stock identity from general species care and narrows broad tolerance ranges into practical home-aquarium targets. Taxonomy and habitat were checked against ITIS and FishBase. UK aquarium care, group, water-quality and feeding guidance was checked against the OATA guppy and Molly care sheet. Domestic-line uncertainty was cross-checked with the Fishkeeper Molly profile. Welfare and point-of-sale context was reviewed against current UK Government animal-selling guidance.

For a broader species overview, water-testing reminders and more community planning, read our Molly fish care guide. The live product selector remains the source of truth for current price and availability.