(resized)
Description
Girardinus metallicus, the metallic girardinus, is a Cuban livebearer of about 5 cm in the male and considerably larger in the female, which reaches 9 cm. The male carries a black stripe that runs from the mouth, along the underside of the body, to the gonopodium. It lives in streams, ponds and ditches of stagnant and often brackish water.
It reached the trade in the early twentieth century and disappeared soon after; it reappeared in a Berlin zoo in 1965 and has been kept ever since by specialist breeders. It is very easy to breed as long as soft, acidic water is avoided, and it occasionally turns up in a shop.
Behavior
Peaceful. Part of its range is stagnant and often brackish water, so tankmates are chosen with care. As in the rest of the family, males can chase females without respite: it is best to keep several females per male and dense plants where they can take refuge.
It lives well with hardy corydoras, tetras and small rainbowfish, if the water is fresh and hard; in a brackish set-up, with bumblebee gobies and other small species.
Avoid housing it with soft, acidic water fish, and with those that do not tolerate hard, alkaline water.
Habitat
Girardinus metallicus is endemic to Cuba. It inhabits streams, ponds, lakes and ditches, and prefers clear, stagnant or very sluggish water, often brackish. In the aquarium it suits medium-hard, alkaline water, or brackish.
Details
🌊 Water parameters
🐠 Minimum tank size
Breeding
Very easy with water that is not soft or acidic, and it breeds like other livebearers. Gestation lasts about 24 days and broods of 15 to 30 fry are born. The adults eat the young: the safest course is to move the gravid female to another tank to give birth there and return her afterwards.
The young are large at birth and accept brine shrimp nauplii or powdered flake from day one; they also need some plant matter, such as blanched spinach or spirulina. They grow quickly on two or three meals a day. Small nets and traps are best avoided.
Diet
Omnivorous, with a large plant component: in the wild it eats diatoms, algae, detritus, insect larvae and aquatic plants.
- Staple: flakes or pellets with plenty of plant matter.
- Supplement: small portions of live or frozen food, plus blanched spinach or spirulina.
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 and 24–27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–8 and 23–27 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 6–8 and 22–26 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 6–7 and 23–27 °C.
They share water: pH 7–8 and 26–27 °C.
They share water: pH 6–7.8 and 22–25 °C.
They share water: pH 6–7 and 22–27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6–7 and 24–26 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 6–8 and 22–26 °C.
They share water: pH 6–7 and 24–27 °C.
They share water: pH 6–8 and 22–26 °C.
They share water: pH 6–8 and 22–27 °C.
They share water: pH 6–8 and 24–27 °C.
They share water: pH 6–7.5 and 25–27 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 6.5–8 and 24–26 °C.
They share water: pH 6–8 and 22–26 °C.
They share water: pH 6–7.5 and 22–25 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 6.5–7.5 and 22–24 °C.
They share water: pH 6–7 and 27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 6–8 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 6.5–8 and 22–27 °C.
They share water: pH 7.5–8 and 26–27 °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 6–8 and 22–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 6–7 and 24–27 °C.
They share water: pH 6–7.5 and 26–27 °C.
They share water: pH 6–7 and 23–27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6–7.5 and 23–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 6–7 and 24–27 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 7.5–8 and 24–27 °C.
They share water: pH 7.5–8 and 24–27 °C.
They share water: pH 6–7 and 22–26 °C.
They share water: pH 6–6.5 and 23–27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6.5–7.2 and 22–26 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 6–8 and 25–27 °C.
They share water: pH 6–8 and 22 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6.5–8 and 22–24 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7 and 23–27 °C.
They share water: pH 6–8 and 22–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 7–8 and 22–26 °C.
They share water: pH 6–7.2 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 7–8 and 22–26 °C.
They share water: pH 6–7.2 and 22–26 °C.
They share water: pH 6–7.2 and 24–27 °C.
They share water: pH 6–7.2 and 24–27 °C.
They share water: pH 6–7 and 26–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6–8 and 25–27 °C.
They share water: pH 6–6.5 and 24–27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6–7 and 24–27 °C.
They share water: pH 6–7 and 23–27 °C.
They share water: pH 6–8 and 23–27 °C.
They share water: pH 6–7.2 and 22–27 °C.
They share water: pH 6–7.5 and 23–27 °C.
They share water: pH 6–8 and 24–27 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 6–7.5 and 23–27 °C.
They share water: pH 6–8 and 22–26 °C.
They share water: pH 6–8 and 22–27 °C.
They share water: pH 6–8 and 24–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 7–8 and 22–27 °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 22–27 °C.
They share water: pH 6.5–7.5 and 22–27 °C.
They share water: pH 7–8 and 22–25 °C.
They share water: pH 7.5–8 and 24–27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 7.5–8 and 26–27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 6.5–7.5 and 22–27 °C.
They share water: pH 7.5–8 and 27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6.5–7.5 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 6.5–7.5 and 23–27 °C.
They share water: pH 6.5–7.5 and 23–27 °C.
They share water: pH 7.5–8 and 27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 7–8 and 23–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 6.5–8 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
They share water: pH 7–8 and 22–27 °C.
Sources
- FishBaseFroese, R. and D. Pauly. Editors. 2026. FishBase. World Wide Web electronic publication.
- Seriously FishSeriously Fish. Girardinus metallicus. Ficha de especie; consultada 2026-10.
Water: FishBase gives pH 6-8, 9-19 dH and 22-25 °C; Seriously Fish, pH 6.5-8, 8-20 dGH and 22-27 °C. The wider range is used: pH 6-8, 8-20 dGH and 22-27 °C. Size: FishBase gives the male 5.0 cm TL and the female 9.0 cm TL; Seriously Fish, 60 mm SL. Tank: Seriously Fish asks for a 45 × 30 cm base (41 l). Salinity: FishBase lists it as freshwater and Seriously Fish says the water is commonly stagnant and often brackish; the profile treats it as freshwater. Name: there is no common name in real use in Spanish; the profile uses the binomial. In English, FishBase calls it «Metallic livebearer» and Seriously Fish, «metallic girardinus».
Litres per fish and minimum tank height and depth: the profile's own judgement. Seriously Fish gives only the tank base and FishBase gives no tank sizes.
Lifespan: the profile's own estimate; the sources consulted do not give it.
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