Metallic Topminnow (Girardinus metallicus)

Overview

Metallic Topminnow (Girardinus metallicus) is a small Cuban poeciliid livebearer also sold as the Metallic Livebearer or, in some hobby strains, the Black-Chin Livebearer. The fish supplied under SKU 6035 are normally around 3-4 cm, with females capable of growing larger than males. It is a lively, surface-leaning livebearer for keepers who like small species with visible behaviour rather than a big show fish.

This is a specialist small livebearer for mature planted aquariums, hard to moderately hard water, a proper group, surface cover and a diet with algae, detritus-style grazing and small invertebrate foods. It suits keepers who want an unusual species with natural movement and colony behaviour, not a generic community filler fish.

Exact Fish And Photo

This listing now includes the original reference photo for SKU 6035 alongside the existing planted-aquarium images. The source photo shows the real slender topminnow shape, metallic sheen and darker male underside that buyers should expect from this line.

Appearance

Girardinus metallicus has a streamlined body, a superior mouth and rounded fins. Under good light the body can show a silver, gold or olive metallic sheen. Males are smaller, slimmer and often more striking, especially black-chin forms where dark pigment runs from the mouth along the underside and gonopodium. Gold-bellied forms also occur in the hobby. Females are larger and fuller-bodied, usually more subtle in colour but still reflective along the flanks.

FishBase gives maximum size as about 5 cm for males/unsexed fish and up to about 9 cm total length for females, so do not plan the aquarium as if the 3-4 cm supply size is the full adult size. Healthy fish should be alert, bright-eyed and active near the upper and middle water levels.

Natural Habitat

FishBase places the species in freshwater habitats in Cuba, with ponds, lakes and streams listed as natural habitat and clear, stagnant or very sluggish water preferred. GBIF also records the accepted taxon as Girardinus metallicus Poey, 1854 in Poeciliidae and lists Metallic Topminnow as an English common name. British Livebearer Association notes streams, ponds and ditches, often stagnant and sometimes brackish, with medium-hard alkaline water working well in aquaria.

The aquarium translation is not a fast river tank. Think mature planted water, gentle movement, surface cover, clean filtration and stable minerals. Avoid soft acidic setups, bare tanks and boisterous communities that make small livebearers hide.

Quick Facts

• Scientific name: Girardinus metallicus
• Common names: Metallic Topminnow, Metallic Livebearer, Black-Chin Livebearer
• Family: Poeciliidae
• Supplied size: Around 3-4 cm for SKU 6035
• Adult planning: Males around 5 cm; females can approach 9 cm
• Temperament: Peaceful, active, males can be persistent with females
• Diet: Omnivore; algae/detritus grazing plus small live, frozen and prepared foods
• Best setup: Planted hard-water species group or very calm small-fish community

Aquarium Setup

A planted aquarium of 60 litres or more works for a small group, while a larger footprint is better if you want a stronger colony or mixed community. Use sand or fine gravel, plants such as Vallisneria, hornwort, Java fern, Cryptocoryne and floating cover, and leave open swimming room near the top. A sponge filter or gentle flow is ideal because the fish appreciate oxygen and cleanliness without being blasted around.

Keep a secure lid. Like many small livebearers, they can jump when startled. A ratio with more females than males helps reduce pressure from persistent males, and plant cover gives females and fry somewhere to rest.

Feeding

FishBase lists diatoms, algae, detritus, insect larvae and aquatic vegetation in the natural diet, so this species should not be fed as a purely meaty micro-predator. Use fine flakes or micro granules, spirulina or algae flakes, crushed vegetable-rich foods and small frozen or live foods such as daphnia, baby brine shrimp and mosquito larvae. Small portions keep the water clean and suit their grazing style.

Behaviour And Tank Mates

Metallic Topminnows are peaceful and social, but they are active livebearers rather than still display fish. Keep a group so their behaviour is spread naturally. They can share a tank with other calm small fish that like similar hard, alkaline water, but avoid fin nippers, larger predators, very soft-water fish and anything that will outcompete them at feeding time. Adult shrimp may work in planted tanks, but tiny shrimplets and fry can be eaten.

Breeding Notes

This is a livebearer and can breed readily once settled. British Livebearer Association notes male persistence and recommends more females than males, with plant cover for fry. Gestation is usually around a month, and fry are large enough for fine powdered foods and newly hatched brine shrimp. If you want to keep numbers controlled, plan ahead before building a colony.

Delivery And Ordering

Order when the aquarium is mature, stable and ready for small livebearers. Tropical Fish Co ships livestock with insulated packing, weather-aware dispatch and a Live Arrival Guarantee. New customers can use WELCOME10 for 10% off their first eligible order. If weather or route conditions are unsuitable, we prioritise the fish and hold dispatch until shipping is safer.