Girardinus metallicus

Metallic Girardinus

Classification

Poeciliidae

Distribution

Costa Rica, Cuba.

Habitat

It can be found in streams, ponds and ditches. The water is commonly stagnant and often brackish.

Maximum Standard Length

Male 30-40 mm, female 40-60 mm.

Aquarium SizeTop ↑

18″ x 12″ x 12″ (45x30x30cm)

Maintenance

A well-planted tank with some floating cover is ideal for this species. Water should be medium hard and alkaline or brackish.

Water Conditions

Temperature: 72-81°F (22-27°C)

pH: 6.5-8.0

Hardness: 8-20 dH

Diet

Omnivorous and the diet should include small frozen, live and dried foods with a high vegetable content.

Behaviour and CompatibilityTop ↑

Peaceful but does appreciate brackish conditions, so tankmates should be chosen with care. If keeping in hard freshwater, then hardy corydoras, tetras and small rainbowfish are good choices. In a brackish setup G. metallicus can be kept with bumblebee gobies and other small species.

Sexual Dimorphism

Males possess a gonopodium and are smaller in size than females. Male fish also have a black ‘stripe‘ which runs from the mouth along the underside of the fish into the gonopodium.

Reproduction

Very easy if soft, acidic water conditions are avoided. Reproduces in standard livebearer fashion. As with other species, the males can be somewhat incessant in their pursuit of females, so we recommend that several females should be kept to every male in order to dissipate this. Areas of dense planting will also help. Gestation takes around 24 days and broods of between 15-30 fry can be expected. The adult fish will predate on the young so the best method of raising them is to remove the gravid female to a separate tank and allow her to give birth there, before returning her to the main aquarium. The use of breeding nets or traps is not recommended as their small size is not suitable for raising fry. The fry are quite large and will accept brine shrimp nauplii or powdered flake from birth. They should also be fed vegetable matter such as blanched spinach or spirulina. They grow very quickly if fed 2-3 times per day.

NotesTop ↑

This species was introduced into the aquarium trade in the early 20th century but disappeared soon after. It subsequently reappeared in a Berlin zoo in 1965 and has been available from specialist breeders ever since. It occasionally appears for sale in aquatic shops.