Neon tetra
Paracheirodon innesi · family Characidae
The neon tetra (Paracheirodon innesi) is a peaceful, 1.4-inch freshwater fish from the western and northern Amazon basin, and it's easy to care for once its tank is set up properly. It's a middle-level swimmer that does best in a group of 6 or more in at least 10 gallons, in soft, slightly acidic water. The most important thing to know is that neon tetras are very sensitive to ammonia and nitrite, so they belong only in a cycled, mature tank.
Edited by Marin Hale · last reviewed October 29, 2026 · How we check facts
Great for beginnersTropicalMature tank onlyNano tank OKGroups of 6+
What can live with a neon tetra?
Verdicts against every species in our database, from our compatibility rules. How verdicts work
| Verdict | Species | Why | Tank |
|---|---|---|---|
| Good match | Ember tetra | No problems found: water, size, fins and temperament all check out. | 10 gal+ |
| Good match | Another neon tetra | No problems found: water, size, fins and temperament all check out. | 10 gal+ |
| Good match | Pygmy corydoras | No problems found: water, size, fins and temperament all check out. | 10 gal+ |
| Good match | Tiger barb | No problems found: water, size, fins and temperament all check out. | 30 gal+ |
| Maybe | Angelfish | Temperatures barely overlap (75–77°F), leaving no margin. | 30 gal+ |
| Maybe | Betta fish | Usually fine with a group of 6+ neons, but stressed neons can nip and some bettas chase them. | 20 gal+ |
| Maybe | Cherry shrimp | Neon tetras eat baby shrimp and may pick off adults. Dense plants and moss help a colony survive. | 10 gal+ |
| Maybe | Guppy | pH ranges only just overlap (7.0–7.0), so one of them will be outside its comfort zone if your water drifts. | 10 gal+ |
| Maybe | Zebra nerite snail | pH ranges don't overlap (6.0–7.0 vs 7.2–8.4). | 10 gal+ |
| Avoid | Common goldfish | Common goldfish need cool water; neon tetras need tropical water. | — |
| Avoid | Fancy goldfish | Fancy goldfish need cool water; neon tetras need tropical water. | — |
Setup and care
| Heater | Yes. Set an adjustable heater to 72–76°F (22–24°C); neon tetras tolerate 70–77°F, and most rooms are cooler than that. |
|---|---|
| Feeding | Small flakes plus brine shrimp, daphnia, bloodworms, micropellets |
| Substrate | Sandy substrate with driftwood and leaf litter looks best |
| New tanks | Add only to an established, cycled tank. Not for a brand-new setup. |
| Males vs females | Male slender with straight blue line; female rounder with bent blue line |
| Breeding | Difficult to breed in home aquariums |
Watch out for
- Susceptible to neon tetra disease, generally incurable and often fatal
- Quarantine newly acquired fish
- Commercial stock often has defects and poor health; choose carefully
- Susceptible to neon tetra disease, virtually untreatable once advanced
- Does best under fairly dim lighting
- Modern neon tetras are less hardy than older stock
Care tips
- Cycle your tank fully before adding neons, because they are very sensitive to ammonia and nitrite.
- Keep the water soft and slightly acidic (pH 6.0–7.0, 1–11 dGH, 0–3 dKH), since neon tetras are not suited to hard, alkaline water.
- Choose your fish carefully, quarantine new arrivals for 2–4 weeks, and acclimate them slowly by the drip method, as modern neons are less hardy than older stock and neon tetra disease is generally incurable and often fatal.
- Use fairly dim lighting and a sandy substrate with driftwood and leaf litter, which looks best and suits this fish.
Questions
Do neon tetras need a heater?
Neon tetras tolerate 70–77°F, and 72–76°F is ideal. If your tank stays in that range without one, you may not need a heater; if it doesn't, you'll need a way to hold it there.
What do neon tetras eat?
Neon tetras are omnivores. Small flakes make a good staple, and you can add brine shrimp, daphnia, bloodworms and micropellets.
What fish can live with neon tetras?
Ember tetras, pygmy corydoras, tiger barbs and other neon tetras all get an "ok" from us. Bettas, guppies, angelfish, cherry shrimp and zebra nerite snails come with cautions, such as mismatched water chemistry, chasing or being eaten. Common and fancy goldfish are a no, because they need cool water and may eat neons.
How many neon tetras should I keep together?
Keep at least 6 together in a tank of 10 gallons or more. They stay small, at about 1.4 inches as adults, and can live 5–8 years with good care.
How can I tell male and female neon tetras apart, and can they be bred?
Males are slender with a straight blue line, while females are rounder with a bent blue line. Neon tetras are difficult to breed in home aquariums.
Sources
Each value is cross-checked across the references below. Where they disagreed, an editor chose a value and recorded why.
- Neon tetra (en.wikipedia.org)
- Paracheirodon innesi (Seriously Fish) (www.seriouslyfish.com)
- Neon Tetra Care: Everything You Need to Know! (glassboxdiaries.com)
- Black neon tetra - Hyphessobrycon herbertaxelrodi (en.aqua-fish.net)
- Neon Tetra: In-Depth Care Profile - JoJo Aquatics (jojoaquatics.com)
- GBIF taxonomy record
- Wikidata entry
Where each value comes from (22 facts)
| Fact | What each source says |
|---|---|
| Temperature | en.wikipedia.org: “with a temperature range of between 72–76 °F (22–24 °C)” seriouslyfish.com: “Temp 21–25°C70–77°F” glassboxdiaries.com: “Temperature 20–26°C (68–80°F)” jojoaquatics.com: “Temperature: 70–77 °F (21–25 °C).” |
| pH editor decision | en.wikipedia.org: “a water pH of between 6.0 and 7.0” seriouslyfish.com: “pH 4.0–7.5” glassboxdiaries.com: “pH 4.0–7.5” jojoaquatics.com: “pH: 6.0–7.0.” |
| Adult size | en.wikipedia.org: “The neon tetra grows to approximately 4 cm (1.6 in) in overall length.” seriouslyfish.com: “Max size 30mm SL1.2in SL” glassboxdiaries.com: “Adult neon tetras typically reach around 4 cm (1.6 inches) in length” jojoaquatics.com: “Adult Max Size 1–1.25 in (25–30 mm)” |
| Lifespan editor decision | en.wikipedia.org: “normally just two to three years in an aquarium” jojoaquatics.com: “Lifespan 5–8 years” |
| Smallest tank editor decision | en.wikipedia.org: “easy to keep in an aquarium of at least 10 US gallons (38 L; 8.3 imp gal)” seriouslyfish.com: “Volume ~54litres~14US gal” glassboxdiaries.com: “Minimum Tank Size 38 litres (10 US gallons)” jojoaquatics.com: “A 20-gallon (~75 L) aquarium is the recommended minimum for a proper school of Neon Tetras” |
| Group size editor decision | en.wikipedia.org: “must be kept in groups of at least six, but will be more active in groups of eight to 12 or more” seriouslyfish.com: “Try to buy a mixed-sex group of at least 8-10 specimens” glassboxdiaries.com: “Minimum Group Size 6 (10+ recommended)” jojoaquatics.com: “should be kept in groups of at least 8–10 individuals” |
| Care level | en.wikipedia.org: “Neon tetras are considered easy to keep in an aquarium” seriouslyfish.com: “Difficulty 6 of 8 measures Easy” glassboxdiaries.com: “Difficulty Beginner” jojoaquatics.com: “Care Level Easy” |
| Diet | en.wikipedia.org: “Neon tetras are omnivores and will accept most flake foods” seriouslyfish.com: “Likely to be omnivorous feeding on small invertebrates, crustacea, filamentous algae, fallen fruit” glassboxdiaries.com: “Diet Omnivore” jojoaquatics.com: “Neon Tetras are micropredator omnivores.” |
| Water type | en.wikipedia.org: “The neon tetra (Paracheirodon innesi) is a species of freshwater fish” |
| Native to | en.wikipedia.org: “found in the western and northern Amazon basin in southeastern Colombia, eastern Peru, and western Brazil” seriouslyfish.com: “a small characid from the Amazon basin in Colombia, Brazil and Peru, found in acidic forest streams” jojoaquatics.com: “Origin Upper Amazon basin (Brazil, Peru, Colombia)” |
| Hardness (GH) | en.wikipedia.org: “GH of below 10 dGH” seriouslyfish.com: “Hardness 1–12dGH” glassboxdiaries.com: “GH 1–12 dGH” jojoaquatics.com: “GH: 1–10 dGH” |
| Carbonate hardness (KH) | en.wikipedia.org: “KH of 1–2 dKH” jojoaquatics.com: “KH: 0–4 dKH.” |
| Telling males from females | en.wikipedia.org: “The male is slender, and the blue line is straighter. The female is rounder, producing a bent blue line.” seriouslyfish.com: “Sexually mature females are normally noticeably rounder-bodied and a little larger than males.” |
| Feeding | en.wikipedia.org: “will accept most flake foods, if sufficiently small, but should also have some small foods such as brine shrimp, daphnia” seriouslyfish.com: “does best when offered a varied menu which in this case should also contain live and frozen chironomid larvae (bloodworm), mosquito larvae, Daphnia, Moina” jojoaquatics.com: “Feed small amounts two to three times daily, only what is consumed within two minutes.” |
| Breeding | en.wikipedia.org: “Breeding neon tetras is considered to be difficult in home aquariums.” seriouslyfish.com: “the adults will eat the eggs given the chance and should be removed as soon as eggs are noticed” jojoaquatics.com: “Adults must be removed promptly after spawning as they will consume the eggs.” |
| Temperament | seriouslyfish.com: “Generally peaceful making it an ideal resident of the well-researched community aquarium.” glassboxdiaries.com: “Temperament Peaceful” jojoaquatics.com: “The Neon Tetra is a peaceful, gregarious schooling fish” |
| Substrate | seriouslyfish.com: “perhaps looks best in an arrangement comprising a sandy substrate plus some driftwood roots and branches” glassboxdiaries.com: “neon tetras have no specific substrate requirements” jojoaquatics.com: “Replicate their native blackwater environment with a fine sand substrate, plenty of driftwood” |
| Swims | glassboxdiaries.com: “Swimming Level Mid-water” |
| Eats shrimp/snails editor decision | glassboxdiaries.com: “A species that can be kept alongside many popular community fish, shrimp and snails.” |
| Safe with plants | glassboxdiaries.com: “Planted Tank Safe? Yes” |
| Mature tank only | glassboxdiaries.com: “Before adding any neon tetras, make sure your aquarium has completed the nitrogen cycle.” |
| Fin-nipper editor decision | jojoaquatics.com: “Avoid larger, fin-nipping, or predatory species” |
Editor decisions (6)
- Farm-bred neons sold today do best at 6.0–7.0 (Wikipedia, Jojo Aquatics); Seriously Fish's 4.0–7.5 includes wild habitats.
- Wikipedia says 2–3 years is typical in aquariums, often because of poor conditions; Jojo Aquatics gives 5–8 years with good care.
- 10 gallons is the common minimum for a group of 6; Seriously Fish and Jojo Aquatics suggest more room (14–20 gal).
- Sources range from 6 to 8; 6 is the common minimum.
- Neons are kept with shrimp and snails (Glass Box Diaries); they may eat newborn shrimp.
- Neons are not fin-nippers; stressed groups can occasionally nip, covered in specific pair notes.