Description
Belonesox belizanus, the top minnow, is a predatory poeciliid, the one that least resembles an ordinary aquarium fish of its family. It reaches 20 cm, has an elongated body and a mouth full of teeth, and it is piscivorous: as soon as something fits in its mouth, it is food. It is native to Central America, from Veracruz in Mexico to Costa Rica.
It is a fish for someone who wants a predator and has the room. It has no place in a community tank. There are populations outside its native range, and so, more than with other fish, an aquarium specimen is never released.
Behavior
It does not attack out of temperament: it is a predator, and what it does with other fish is eat them. In a tank with small fish, cohabitation ends badly. Compatibility is decided by size: whatever fits in its mouth is not company. The safest course is to keep it alone or as a pair, in a roomy tank.
It lives well with robust fish of similar or larger size, only in a very large tank with plenty of space.
Avoid housing it with any small fish, shrimp or snail, or with long-finned fish.
It does not spare its own young either: they are separated as soon as they are born.
Habitat
Belonesox belizanus lives in Central America, from Laguna San Julián, northeast of Veracruz in Mexico, to Costa Rica, along the southern Gulf of Mexico, southern Yucatán and the Central American coast. Adults occupy weedy canals and tolerate poorly oxygenated water and a salinity of up to 40 ppt well.
It is mainly a freshwater fish, and sometimes a brackish-water one. Its presence in salt water in Florida (34-37 ppt) seems to be a local acclimatisation, not a preference.
Details
🌊 Water parameters
🐠 Minimum tank size
Breeding
A livebearer, like the rest of the family: up to a hundred embryos per female. As a predator of fish, it devours its own young and anyone else's, so the young are separated as soon as they are born.
There is no data on the length of gestation or on breeding in the aquarium.
Diet
Piscivorous: in the wild it hunts fish. In the aquarium it needs whole prey, whether fish of a suitable size or pieces of frozen fish; live feeder fish can bring disease.
- Staple: fish and whole prey, frozen.
- Supplement: a healthy live prey now and then.
What about your tank?
Enter your tank's values to see only the compatible species that fit them. Litres apply to fish.
Compatible fish
General guidance based on water parameters, behaviour and known exceptions; always review the individual animals' and aquarium's specific needs.
They share water: pH 6–7.5 and 25–27 °C.
They share water: pH 6–8 and 25–30 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–8 and 25–26 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7 and 25–30 °C.
They share water: pH 7–8 and 26–30 °C.
They share water: pH 6–7.8 and 25 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6–7.5 and 25–27 °C.
They share water: pH 6–7.5 and 25–27 °C.
They share water: pH 6–7.5 and 25–27 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–8 and 25–26 °C.
They share water: pH 6–7 and 25–27 °C.
They share water: pH 6–8 and 25–26 °C.
They share water: pH 6–8 and 25–30 °C.
They share water: pH 6–8 and 25–30 °C.
They share water: pH 6–7.5 and 25–30 °C.
They share water: pH 6–7.5 and 25–30 °C.
They share water: pH 6.5–8 and 25–26 °C.
They share water: pH 6–8 and 25–26 °C.
They share water: pH 6–7.5 and 25 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–8 and 25–35 °C.
They share water: pH 6–8 and 25–27 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 6.5–8 and 25–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–8 and 25–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7 and 25–28 °C.
They share water: pH 6–7.5 and 26–30 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 25–27 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 6–7 and 25–30 °C.
They share water: pH 6–7.5 and 25–26 °C.
They share water: pH 7.5–8 and 25–28 °C.
They share water: pH 7.5–8 and 25–28 °C.
They share water: pH 6–7 and 25–26 °C.
They share water: pH 6.5–7.2 and 25–26 °C.
They share water: pH 6–7.5 and 25–26 °C.
They share water: pH 6.5–7.5 and 25–26 °C.
They share water: pH 6.5–7.5 and 25–26 °C.
They share water: pH 6.5–7.5 and 25–26 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7 and 25–28 °C.
They share water: pH 6–8 and 25–27 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 7–8 and 25–26 °C.
They share water: pH 6–7.2 and 25–28 °C.
They share water: pH 7–8 and 25–27 °C.
They share water: pH 7–8 and 25–26 °C.
They share water: pH 6–7.2 and 25–26 °C.
They share water: pH 6–7.2 and 25–28 °C.
They share water: pH 6–7.2 and 25–28 °C.
They share water: pH 6–7 and 26–30 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7 and 25–26 °C.
They share water: pH 6.5–7.5 and 25–26 °C.
They share water: pH 6–8 and 25–29 °C.
They share water: pH 6–7 and 25–28 °C.
They share water: pH 6–7 and 25–28 °C.
They share water: pH 6–8 and 25–27 °C.
They share water: pH 6–7.2 and 25–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–8 and 25–28 °C.
They share water: pH 6–7.5 and 25–26 °C.
They share water: pH 6–7.5 and 25–27 °C.
They share water: pH 6–8 and 25–26 °C.
They share water: pH 6–8 and 25–28 °C.
They share water: pH 6–8 and 25–27 °C.
They share water: pH 6–7.5 and 25–27 °C.
They share water: pH 7–8 and 25–28 °C.
Compatible invertebrates
General guidance based on water parameters, behaviour and known exceptions; always review the individual animals' and aquarium's specific needs.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 6.5–7.5 and 25–27 °C.
They share water: pH 7–8 and 25 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 6.5–7.5 and 25–26 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 6.5–7.5 and 25–27 °C.
They share water: pH 6.5–7.5 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 6.5–7.5 and 25–28 °C.
They share water: pH 6.5–7.5 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 6.5–7.5 and 25–26 °C.
They share water: pH 6.5–7.5 and 25–26 °C.
They share water: pH 6.5–7.5 and 25–26 °C.
They share water: pH 6.5–7.5 and 25–26 °C.
They share water: pH 6.5–7.5 and 25–26 °C.
They share water: pH 6.5–7.5 and 25–26 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 6.5–8 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
They share water: pH 7–8 and 25–28 °C.
Sources
- FishBaseFroese, R. and D. Pauly. Editors. 2026. FishBase. World Wide Web electronic publication.
The care values (pH, temperature and hardness) come from a single source: none of the other accepted sources records them for this species.
Water: FishBase gives pH 6-8, 9-19 dH and 25-37 °C; the profile's ranges are its own. Seriously Fish has no profile of the species (404). Size: 20.0 cm TL in FishBase, which also cites 14 cm total length. Salinity: FishBase lists it as freshwater and brackish, mostly freshwater and sometimes brackish, tolerating a salinity of up to 40 ppt; the profile admits fresh or brackish. Diet: FishBase gives it as piscivorous. Breeding: FishBase records up to 100 eggs, which in a livebearer are the embryos. Name: «pez aguja» is the common name chosen for the profile; FishBase calls it «Top minnow» in English.
Litres per fish, tank sizes and lifespan: the profile's own judgement. The sources consulted do not give them.
Plan your next aquarium
Is this fish right for you? Plan a suitable aquarium before setting it up.