Home / Fishes / Killifish and livebearers / Sail-fin molly
No federal permit to keepSail-fin molly
Poecilia velifera
Fishes › Killifish and livebearers (Cyprinodontiformes) › Poeciliidae (Livebearers)
Poecilia velifera, commonly known as the Yucatán molly or giant sailfin molly, is a poeciliid fish native to the Yucatán Peninsula in Mexico.
Care at a glance
Species-specific aquarium care
- Tank: At least 30 in long and 12 in front to back for one adult (adults commonly reach about 5.9 in / 15 cm).
- Water: Freshwater (tolerates brackish).
- Temperature: 77–82°F (range recorded for this species).
- pH: 8–8.
- Hardness: 13–19 dGH.
- Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
- Diet: Eats a varied diet: mix quality prepared foods with frozen and live foods. FishBase classes it as a omnivore.
Calculated from this species' own FishBase record: tank size from its typical adult length and swimming zone, water values from its recorded ranges. The group guide below fills in general care.
Care guide
Species care notes
- Tank: a base of at least 36 × 15 in (roughly 27 US gallons); space needed is rated “large tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 72–82 °F, pH 7–8.5, 15–35 dGH.
- Behaviour: temperament peaceful.
- Difficulty: Easy (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Ideally a heavily-planted setup with some floating cover and areas of open water.”
- Diet: “Omnivorous by nature, feeding on a variety of zoobenthos and detritus in the wild.”
- Tankmates: “A peaceful fish in a community aquarium but should only be kept with other species that can tolerate hard water.”
- Breeding: “Relatively difficult compared to some livebearers.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Livebearers (guppies, mollies, platies and swordtails)
Applies to most species in this group. Habitat: Warm streams, ponds and brackish waters. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Planted tanks with gentle flow; mollies appreciate harder, slightly brackish water.
Diet
- Flake foods with plant matter, plus live or frozen foods.
Social life
- Peaceful community fish; keep more females than males.
Health watch
- They breed constantly; plan for fry or keep single-sex groups.
Understanding the animal
About this animal
About this animal
It is typically under 10 cm (3.9 in) in length, but may reach 15 cm (5.9 in), with males somewhat larger than females. It belongs to a group of mollies known as sailfins, named for the large males' sail-like dorsal fin, a feature that is especially pronounced in P. velifera.
Quoted from the Wikipedia article “Poecilia velifera” (CC BY-SA 4.0) 174
In the wild
In the wild
From this species’ own FishBase record (habitat, bottom type, water and breeding data), not its family. Good care copies these conditions.1
| Where it lives | Lives in freshwater and brackish water. Uses both the bottom and open water. Feeds on worms, crustaceans, insects and plant matter. |
| Water it lives in | Freshwater / brackish water, 77–82 °F (25–28 °C), pH 8–8, hardness 13–19 dH. |
| Climate | Tropical climate. |
| Behavior to plan for | Breeding: internal live bearers. |
What this means for care
- Keep water within its wild range, 77–82 °F.
- It tolerates or needs brackish water; check salinity needs before setup.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 95°F (up to 97°F in the hottest sampled areas) |
| Cool-season lows | about 63°F (down to 60°F in the coldest sampled areas) |
| Average temperature | 78–80°F across sampled records |
| Relative humidity | 75–79% on average (driest month about 68%) |
| Rainfall | about 1165 mm a year |
Measured at 34 wild occurrence records sampled against WorldClim 2.1 climate data (1970–2000 averages). Air conditions in the range are ecological context, not enclosure settings: microhabitats such as burrows, leaf litter or basking rocks can be cooler, warmer or more humid.
From the sources
From the sources
Quoted from the matching sections of reputable sources for this exact species. Specialist databases are used first; Wikipedia (community-edited, CC BY-SA 4.0) only fills gaps. Other sources are short credited quotes.
| Overview | Poecilia velifera, commonly known as the Yucatán molly or giant sailfin molly, is a poeciliid fish native to the Yucatán Peninsula in Mexico. It is typically under in length, but may reach, with males somewhat larger than females. It belongs to a group of mollies known as sailfins, named for the large males' sail-like dorsal fin, a feature that is especially pronounced in P. velifera. — Wikipedia (community-edited) |
| Where it lives | Home ranges Population dynamics Growth parameters Max. ages / sizes Length-weight rel. Length-frequencies Mass conversion Recruitment Abundance Life cycle Reproduction Maturity Maturity/Gills rel. — FishBase |
| Appearance and size | Maximum length 15.0 cm tl male/unsexed. — FishBase |
| Biology | Adults feed on worms, crustaceans, insects and plant matter. Migratory behaviour is undetermined. Aquarium keeping: minimum aquarium size 60 cm. — FishBase |
| History and naming | Yucatán mollies were misidentified in the early twentieth century as Mollienesia latipinna, with records from Progreso, Yucatán, and Isla Mujeres in 1902, from La Vega in Yucatán (misattributed to Tamaulipas) in 1904, and from a ciénega wetland near Progreso in 1906. — Wikipedia (community-edited) |
Data and studies
The numbers
The numbers
Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.
Adult length
Maximum recorded length. Measured as total length. Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates in nature; aim for the middle.
Minimum tank footprint
Seriously Fish recommends a tank base of at least 36 × 15 in (about 27 US gallons).
Sources for this sheet
- FishBase (Froese & Pauly, eds.), version 24.07 Peer-reviewed researchThe global scientific database on fishes, maintained by a consortium of research institutions; every value is referenced.
- Seriously Fish species profiles Experienced keeper or breederLong-running aquarium reference written and peer-checked by experienced fishkeepers and ichthyologists; each profile covers habitat, tank size, water, diet, behaviour and breeding.
- Merck Veterinary Manual: Management of aquarium fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Types and features of aquatic systems Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Nutritional diseases of fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.
- iNaturalist (captive observations) Community referenceCommunity observation platform run by the California Academy of Sciences and National Geographic; observations marked captive show animals living in homes, zoos and aquariums.
More livebearers
Blackbelly limia
Limia melanogaster
Aquarium hobby
Dusky millions fish
Phalloceros caudimaculatus
Aquarium hobby
Endlers guppy
Poecilia wingei
Aquarium hobby
Green swordtail
Xiphophorus hellerii
Aquarium hobby
Guppy
Poecilia reticulata
Aquarium hobby
Humpbacked limia
Limia nigrofasciata
Aquarium hobby