Green fire tetras with shrimp

By the Shrimp Tank Hub editorsUpdated Oct 28, 2026Research-based

The green fire tetra, also sold as Rathbun's bloodfin or Rathbun's tetra, is Aphyocharax rathbuni, a small characin from the Paraguay, Paraná and Uruguay river drainages in Brazil, Paraguay, Argentina and Uruguay (Seriously Fish). It has been sold under the old name A. stramineus (Maidenhead Aquatics). In the wild it lives in streams and rivers shaded by floating or overhanging plants (Seriously Fish), and Maidenhead Aquatics says it comes from a huge variety of habitats along tributaries of the Rio Paraguay that change a lot with the seasons, which helps explain why it adapts to a wide range of aquarium conditions. In the Pantanal wetlands, Practical Fishkeeping watched shoals moving through newly flooded vegetation grazing on algae and suggests that diet may be the source of their intense green color. It is a close cousin of the bloodfin tetra and shares its fast, slightly nippy habits.

Green fire tetra at a glance

Will green fire tetras eat shrimp?

• Adult shrimp: some risk. None of our sources tested green fire tetras with shrimp. Aquarium Co-Op says to avoid medium to large fish with cherry shrimp, and Practical Fishkeeping's Nathan Hill personally counts the larger tetras among fish that will eventually eat shrimp. In our reading, a fast, nippy fish of nearly 2 inches will pick at small males and freshly molted cherries.
• Shrimplets: expect them to be eaten. Neale Monks at Practical Fishkeeping says pretty much any active fish, even one as small as a tetra, views hatchling shrimp as food.
• Eggs and berried females: eggs are safe while carried under the tail.

Dense moss and plants let some babies survive (Aquarium Co-Op), but a group of active tetras will thin out each hatch. For lower-risk tetras, compare ember tetras with shrimp and flame tetras with shrimp; for its closest relative, see bloodfin tetras with shrimp, or browse the full cherry shrimp tank mates list.

Matching the water

Seriously Fish lists 68–79 °F, pH 6.5–7.5 and 2–20 dGH. Maidenhead Aquatics gives 20–26 °C and pH 6.0–7.0 with hardness up to 18 dH, says the species acclimatizes to a wide range of conditions, and advises avoiding extremes. The Shrimp Farm lists 65–80 °F, pH 6.8–8.0 and GH 4–8 for cherry-type shrimp. By our comparison, the overlap is about 68–79 °F, pH 6.8–7.5 and GH 4–8, or pH 6.8–7.0 if you follow Maidenhead Aquatics; we'd aim for about 70–76 °F and pH 6.8–7.2. Like cherry shrimp, this tetra doesn't need a warm tank. See shrimp tank pH, GH and KH explained and shrimp tank temperature.

Tank size and setup

• Size: Seriously Fish says a base of 24 × 12 in (about 14 US gallons) suits a small group.
• Planted, with shade: Seriously Fish recommends a well-planted tank with a sandy substrate, bogwood, roots and pebbles, and moderate water flow; lighting isn't critical. Maidenhead Aquatics suggests plenty of shade from bogwood and plants, including floating plants, and says the fish show their best colors once settled in a secure, planted tank. Thick moss gives shrimp cover (Aquarium Co-Op). See java moss for shrimp and driftwood and botanicals for shrimp.
• Shrimp-safe intake: a sponge filter or pre-filter keeps shrimplets out of the intake (our suggestion). See shrimp-safe filters.
• Start mature. See how to cycle a shrimp tank.

Group size and behavior

Seriously Fish says to keep at least 6. Maidenhead Aquatics says 6 or more, ideally with more females than males. Males are more brightly colored, with white tips to the dorsal, anal and pelvic fins, and females are fuller-bodied when ready to spawn (Maidenhead Aquatics, Seriously Fish). Maidenhead Aquatics notes that young fish often look drab in shops and the colors improve with age.

Other tankmates

Because of the fin-nipping reputation, Seriously Fish says to choose robust, faster-moving tankmates and to avoid long-finned fish such as many cichlids and anabantoids; Maidenhead Aquatics also says not to trust it with fancy long-finned fish. That rules out bettas in a shrimp tank, which Aquarium Co-Op already warns can go after shrimp. Small catfish are a better fit. See corydoras with shrimp, otocinclus with shrimp and bettas with shrimp.

Feeding both

Seriously Fish says green fire tetras are not fussy and take most aquarium foods, but live or frozen foods should be offered regularly. Maidenhead Aquatics lists flake, micropellets and small frozen foods such as mosquito larvae, brine shrimp and Daphnia. Feed the tetras first, then drop sinking shrimp food into a planted corner so the shrimp eat before the fish find it (our suggestion). See best shrimp food.

How to add green fire tetras to a shrimp tank

• Shrimp first. Practical Fishkeeping suggests letting the shrimp colony build up before adding fish; hiding places and well-fed fish reduce losses.
• Consider bigger shrimp. Neale Monks suggests larger shrimp such as Amanos when the fish are likely to eat babies. See Amano shrimp care.
• Acclimate slowly. See how to drip acclimate.
• Watch shrimp numbers for the first few weeks, especially after molts.
• Quarantine the fish separately. Practical Fishkeeping says many fish medications are not safe for invertebrates. If fish get sick, ask a fish veterinarian or an experienced store about treatment that won't harm the shrimp. See how to quarantine and is copper toxic to shrimp.

Common mistakes

• Judging them by their dull colors in the store; Maidenhead Aquatics says young fish look drab and color up later.
• Keeping only two or three; Seriously Fish and Maidenhead Aquatics both say at least 6.
• Adding long-finned fish such as bettas to the same tank.
• Expecting a cherry colony to grow quickly next to a group of fast tetras.

Track it

Log temperature, pH, GH and TDS on the free Water Parameter Log printable so you can keep the tank in the range both species share.

Frequently asked questions

Will green fire tetras eat cherry shrimp?

They will eat shrimplets, and in our reading small or freshly molted adults are at some risk from a fast, nippy fish of almost 2 inches. We rate them a moderate to high risk.

Is the green fire tetra the same as Rathbun's bloodfin?

Yes. Seriously Fish and Maidenhead Aquatics both list green fire tetra and Rathbun's bloodfin as names for Aphyocharax rathbuni.

How big do green fire tetras get?

About 1.6 to 1.8 inches: 45 mm standard length per Seriously Fish, or 4 cm per Maidenhead Aquatics.

What water do green fire tetras need?

Seriously Fish lists 68 to 79 °F, pH 6.5 to 7.5 and 2 to 20 dGH; Maidenhead Aquatics says they adapt to a wide range. With cherry shrimp, aim for about 70 to 76 °F and pH 6.8 to 7.2 in our reading.

Do green fire tetras nip fins?

Seriously Fish says they have a reputation as fin-nippers and suggests avoiding long-finned tankmates; Maidenhead Aquatics calls them mostly peaceful but not safe with long-finned fish.

How many green fire tetras should I keep?

At least 6 (Seriously Fish); Maidenhead Aquatics says 6 or more, ideally with more females than males.

Sources: Seriously Fish, Aphyocharax rathbuni (green fire tetra) (Aphyocharax rathbuni, green fire tetra or Rathbun's bloodfin; Paraguay, Paraná and Uruguay drainages in Brazil, Paraguay, Argentina and Uruguay; streams shaded by floating or overhanging vegetation; 45 mm SL; base 60 × 30 cm, about 54 L, 14 US gal; 20–26 °C, pH 6.5–7.5, 2–20 dGH; well planted, sandy substrate, bogwood, roots, pebbles, moderate flow, lighting not critical; not fussy, live or frozen regularly; group of at least 6; fin-nipping reputation, robust faster tankmates, avoid long-finned cichlids and anabantoids; females fuller-bodied); Maidenhead Aquatics (fishkeeper.co.uk), Rathbun's bloodfin tetra (Rathbun's bloodfin tetra, also sold as green fire tetra; synonym A. stramineus; Rio Paraguay tributaries with large seasonal changes; 4 cm; 20–26 °C; adapts widely, pH 6.0–7.0, up to 18 dH, avoid extremes; shade from bogwood and plants including floating plants; groups of 6 or more, ideally more females; juveniles drab, colors improve with age; mostly peaceful, not with long-finned fish; males brighter with white fin tips; flake, micropellets, mosquito larvae, brine shrimp, Daphnia); Practical Fishkeeping, Rathbun's tetra in the wild (Pantanal; grazes algae in newly flooded vegetation, possibly the source of its green color); Practical Fishkeeping, can I safely add some shrimp? (Neale Monks: almost any active fish, even a small tetra, eats hatchling shrimp; larger shrimp such as Amanos); Practical Fishkeeping, What can I keep with shrimp? (larger tetras among fish that eventually eat shrimp; let shrimp numbers build first; hiding places; well-fed fish; many medications unsafe for invertebrates); Aquarium Co-Op, Cherry shrimp tank mates (avoid medium to large fish; bettas go after shrimp; moss and plants for baby shrimp); The Shrimp Farm, Red rili shrimp tank set-up and care (cherry-type range 65–80 °F, pH 6.8–8.0, GH 4–8). Risk rating, temperature advice and the shared water range are our reading of these sources.