The Green Fire Tetra (Aphyocharax rathbuni) is also known as Rathbun’s bloodfin, is a hardy, active schooling fish native to South America. Growing to about 4.5–5 cm, they feature a shimmering metallic green body accented by vibrant red on the belly, anal fin, and tail.

Quick Facts:

• Size: Grows up to 4.5 to 5 cm.
• Appearance: Metallic greenish-silver body with a vibrant red or orange lower belly, tail, and fins; males develop distinct white tips on their pelvic and anal fins when mature.

Aquarium Requirements:

• Tank Size: Minimum of 10 to 20 gallons (ideally 20–30+ gallons for a comfortable school).
• Water Parameters:
  • Temperature: 20–28°C
  • pH: 6.0–7.5

Tank Setup & Behaviour:

• • Aquascape: They look dull grey in bare shop tanks, so provide a dark substrate, driftwood, and dense aquatic plants to bring out their emerald sheen. Floating plants help diffuse bright lighting, which matches their shaded river habitats.
  • Tankmates: Pair them with other quick, peaceful community fish like rasboras, corydoras, or similar-sized tetras. Avoid slow-moving or long-finned fish (such as bettas, angelfish, or fancy guppies), as green fire tetras can nip trailing fins—especially if kept in small groups.
  • Diet: As omnivores that feed primarily in the middle and upper water column, they readily accept crushed flakes, micro-pellets, and small frozen or live foods like brine shrimp and daphnia.
  • Sexing & Breeding: Mature males are slimmer and develop distinct white tips on their pelvic and anal fins, while females are rounder with slightly more muted colours. They are egg-scatterers that spawn in dense moss or plants, though parents will eat the eggs unless removed.