Bloodfin tetra care guide
Also called: Red-finned tetra, True bloodfin tetra
The bloodfin tetra is a hardy, fast-swimming silver tetra with bright red fins. It handles a wide range of water and cooler temperatures than most tetras, but it can nip long fins, so keep six or more with short-finned tankmates and a tight lid.
Bloodfin tetras need a tank of at least 20 gallons (76 L), a group of 6 or more, and water at 20–26°C (68–79°F) with a pH of 6–8. They grow to about 5 cm (2 in) and are peaceful.
Plan a tank with bloodfin tetrasSee all tank mates
Bloodfin tetra quick facts
| Scientific name | Aphyocharax anisitsi |
|---|---|
| Family | Characidae |
| Origin | Paraná River basin in Argentina, Paraguay and Brazil (most in shops are captive-bred) |
| Adult size | 5 cm (2 in) |
| Minimum tank | 20 gallons (76 L), at least 60 cm (24 in) long |
| Temperature | 20–26°C (68–79°F) |
| pH | 6–8 |
| Hardness (GH) | 4–20 dGH |
| Group size | 6 or more (schooling fish) |
| Temperament | Peaceful |
| Swims at | Top |
| Diet | Omnivore |
| Care level | Easy |
| Lifespan | 5–8 years |
| Safe with shrimp? | Mostly (eats baby shrimp) |
| Safe with plants? | Yes |
- Known jumper: keep a tight-fitting lid.
Tank setup
A school of six needs at least a 20-gallon (76 L) tank that is 60 cm (24 in) or longer. Longer tanks suit these fast swimmers best. Plant the sides and back and leave a wide open lane for swimming. A tight lid is a must because they jump.
How many bloodfin tetras in a tank?
The smallest common tank that suits bloodfin tetras is a 20 gallon. Here is roughly how many fit in each size when they are the only fish, based on adult size and waste output. Leave room if you want tank mates.
| Tank | Bloodfin tetras (alone) |
|---|---|
| 3 gallon | Too small |
| 5 gallon | Too small |
| 10 gallon | Too small |
| 15 gallon | Too small |
| 20 gallon | 6–19 |
| 20 gallon long | 6–19 |
| 29 gallon | 6–28 |
| 40 gallon | 6–39 |
| 55 gallon | 6–53 |
| 75 gallon | 6–73 |
| 125 gallon | 6–121 |
What you need for bloodfin tetras
Sized for a 20 gallon tank, the smallest common size that suits a group of 6 bloodfin tetras. For a different tank or a mix of fish, use the stocking calculator for a list sized to your plan.
Tank and equipment
- 20 gallon aquarium (tank or kit) (opens Amazon in a new tab)Bigger tanks are more stable and easier for beginners. How to choose
- Aquarium stand for 20 gallons (opens Amazon in a new tab)The water alone weighs about 167 lb (76 kg), before glass, gravel and rock. How to choose
- Adjustable heater, 50 W (opens Amazon in a new tab)Holds about 73 °F (23 °C) in a room at 65 °F (18 °C). How to choose
- Aquarium thermometer (opens Amazon in a new tab)Check it daily: heaters can fail stuck on or off. How to choose
- Hang-on-back filter rated 80–120 GPH (opens Amazon in a new tab)Community tank: 4–6 times the tank volume per hour. How to choose
- About 35 lb of aquarium gravel (opens Amazon in a new tab)Enough for a layer about 2 in (5 cm) deep. Smooth gravel suits most community fish. How to choose
- Water conditioner (dechlorinator) (opens Amazon in a new tab)Removes chlorine and chloramine from tap water. Seachem Prime is a popular, concentrated choice. How to choose
- Liquid test kit (ammonia, nitrite, nitrate, pH) (opens Amazon in a new tab)Liquid kits are more accurate than strips. The API Freshwater Master Test Kit is the common choice. How to choose
- Gravel vacuum (siphon) (opens Amazon in a new tab)Cleans the gravel and does the water change in one go. How to choose
- LED aquarium light, about 24 in long (opens Amazon in a new tab)Match the light to the tank length. Basic LEDs grow easy plants. How to choose
Food and extras for bloodfin tetras
- Micro pellets or flakes for small fish (opens Amazon in a new tab)Small enough for tetras, rasboras and other nano fish.
- Tight-fitting lid for a 20 gallon tank (opens Amazon in a new tab)Bloodfin tetra can jump out of an open tank.
Product links go to Amazon search results. As an Amazon Associate we earn from qualifying purchases, at no extra cost to you. Disclosure.
Water parameters
Comfortable at 20–26 °C (68–79 °F), pH 6.0–8.0 and 4–20 dGH. They come from a subtropical region and cope with cooler water than most tetras, but use a heater if your room drops below about 20 °C (68 °F). Keep ammonia and nitrite at zero with regular water changes.
Best tank mates for bloodfin tetras
These popular species share bloodfin tetras' water needs and temperament. See the full list of 96 good matches.
Cherry shrimp
3 cm (1.2 in) · 20–27°C (68–81°F)
Nerite snail
2.5 cm (1 in) · 22–27°C (72–81°F)
Neon tetra
3.5 cm (1.4 in) · 21–25°C (70–77°F)
Panda corydoras
4.5 cm (1.8 in) · 21–25°C (70–77°F)
Bristlenose pleco
12 cm (4.7 in) · 22–26°C (72–79°F)
Bronze corydoras
7 cm (2.8 in) · 21–26°C (70–79°F)
Zebra danio
5 cm (2 in) · 18–25°C (64–77°F)
Assassin snail
2.5 cm (1 in) · 22–27°C (72–81°F)
Avoid keeping bloodfin tetras with
- Oscar: Oscar can eat bloodfin tetras: they're small enough to fit in its mouth once it's grown.
- Bala shark: Bala shark can eat bloodfin tetras: they're small enough to fit in its mouth once it's grown.
- Chinese algae eater: Chinese algae eater is aggressive and will bully or injure peaceful bloodfin tetras.
- Convict cichlid: Convict cichlid is aggressive and will bully or injure peaceful bloodfin tetras.
- Discus: They need different temperatures: Bloodfin tetra 20–26°C (68–79°F), discus 28–30°C (82–86°F).
- Electric blue acara: Electric blue acara can eat bloodfin tetras: they're small enough to fit in its mouth once it's grown.
Feeding
Easy to feed. Offer a quality flake or small pellet daily, plus frozen or live daphnia, brine shrimp and bloodworm. They grab food fast near the surface, so make sure slower fish get their share.
Behavior
Lively and generally peaceful, they spend most of their time in the upper half of the tank. They may nip slow fish with long fins, such as bettas, fancy guppies and angelfish. A bigger group keeps their energy focused on each other.
Breeding
One of the easier tetras to spawn. Condition a pair or small group on live and frozen food, then move them to a separate tank with fine-leaved plants or a mesh over the bottom. The eggs are not sticky and drop into the plants, so remove the adults straight after spawning. Fry hatch in about a day and start on infusoria, then baby brine shrimp.
Tips from experienced keepers
- Cover every gap in the lid. Bloodfins are strong jumpers.
- Keep them with fast, short-finned fish like danios, rasboras, other active tetras and corydoras.
- Avoid bettas, fancy guppies and angelfish, whose long fins attract nipping.
- A good pick for cooler or harder water, where many soft-water tetras struggle.
- Add some sinking food so bottom dwellers are not outcompeted at feeding time.
Frequently asked questions
Do bloodfin tetras nip fins?
They can, mostly in small groups or with slow, long-finned fish. Keep at least six (more is better) and choose fast, short-finned tankmates.
Do bloodfin tetras need a heater?
They tolerate cooler water than most tetras and do well at 20–26 °C (68–79 °F). If your room falls below about 20 °C, use a heater to keep the temperature steady.
How long do bloodfin tetras live?
Usually 5 to 8 years with good care, and some live past 10 years.
Sources
We checked these references when writing this page. Values are for healthy long-term keeping, not survival limits. Last reviewed 2026-10-13. See our editorial policy.