Metallic Livebearer / Black Chin (Girardinus metallicus) Aquarium Glaser Med-Large

Girardinus metallicus, commonly known as the Metallic Livebearer or Black Chin Livebearer, is a small, striking livebearing fish native to Cuba and Costa Rica. The "metal black" or black chin variant is especially popular for its shimmering body and distinctive dark markings.

Species Overview

• Scientific Name: Girardinus metallicus
• Common Names: Metallic Livebearer, Black Chin Livebearer, Metallic Topminnow
• Size: Males ~3.8 cm (1.5 in), Females ~6.3 cm (2.5 in) 
• Lifespan: 2–3 years
• Distribution: Native to slow-moving or stagnant waters in Cuba and Costa Rica 

Appearance

• Males: Metallic sheen with a black stripe running from under the mouth to the gonopodium (reproductive organ)
• Females: More muted, tan to gold with occasional speckling
• Variants: Includes black chin, yellow belly, and metallic chrome-like strains 

Water Parameters

• Temperature: 22–27°C (72–80°F)
• pH: 7.0–8.0
• Hardness: Moderately hard to hard (up to 20 dGH)
• Salinity: Can tolerate freshwater or low-end brackish conditions

Tank Setup

• Tank Size: 5–10 gallons for a small group
• Substrate: Dark sand or gravel
• Plants: Dense planting with floating species for cover
• Filtration: Gentle flow; sponge filters work well
• Lighting: Dim to moderate (diffused preferred)

Diet

• Type: Omnivorous
• Foods: Crushed flakes, veggie flakes, micro pellets, baby brine shrimp, daphnia, cyclops, and algae-based foods 

Behavior & Compatibility

• Temperament: Peaceful but males can be persistent with females
• Best Kept: In groups with 2–3 females per male
• Tankmates: Small, peaceful species like Celestial Pearl Danios, Corydoras, or dwarf tetras

Breeding

• Type: Livebearer
• Gestation: ~4 weeks
• Fry Count: Up to 30 per brood
• Fry Care: Provide dense cover or separate tank; feed baby brine shrimp or powdered fry food