Black Neon Tetra: tank size, group & compatibility data

Planning profile for Hyphessobrycon herbertaxelrodi.

curated core

Curated StockingLab core profile.

Planning profile

Adult size
~4 cm / 1.6 in
Reference tank
45+ L / 11.9+ US gal
Social group
8+
Swim zone
Mid
Temperament
Peaceful

Water window

Temperature
23–27°C / 73.4–80.6°F
pH
5.5–7.5
Relative waste
0.75×
Activity
1.00×

Stocking notes

A hardy schooling tetra suited to calm community aquariums.

For planning, StockingLab models Black Neon Tetra at its approximate adult size rather than the juvenile size commonly seen in shops. That matters because space use and waste production can change dramatically as fish mature.

What the calculator checks

  • Whether the tank's usable volume is below the 45 L / 11.9 US gal reference minimum.
  • Whether the selected group is below the planner's typical 8 fish social starting point.
  • Whether target temperature and pH sit inside the planning range.
  • Whether prospective tankmates create predation, fin-nipping, territorial or water-overlap conflicts.
  • Whether too many fish accumulate in the same mid swim zone.

Before buying

Use this profile as a shortlist tool, not as a substitute for a dedicated care source. Confirm adult size, diet, sex ratio, habitat structure and locally relevant water conditions before purchase.

How to interpret this Black Neon Tetra profile

At roughly 4 cm / 1.6 in adult length, Black Neon Tetra should be planned at mature size rather than the smaller size commonly offered for sale. The reference tank is 45+ L / 11.9+ US gal, with a planning water window of 23–27°C and pH 5.5–7.5. A midpoint around 25.0°C and pH 6.5 is useful only as a comparison aid; the aim is stable water that overlaps the needs of the whole community.

The profile starts from a social group of 8+ because this is a strongly group-oriented species; planning only one or two would understate both its welfare needs and the space used by a proper group. Its modeled waste factor is relatively modest at 0.75×, but that does not make the 45 L reference tank optional: swimming room, social structure and oxygen demand are separate constraints. Activity is modeled at 1.00×, so the planner balances ordinary movement demand with adult size and mid-zone occupancy.

Common planning mistakes to avoid

  • Keep the group at or above the 8+ planning starting point before adding extra species.
  • Check that the planned temperature sits inside the shared 23–27°C range for every species in the community.
  • Use the 45 L / 11.9 US gal reference as a starting point, then let actual tank dimensions, filtration and the full stock list refine the decision.

Bottom line: the profile is designed to screen a proposed aquarium for obvious pressure points. A result that passes StockingLab still needs to be checked against current, species-specific husbandry information for Hyphessobrycon herbertaxelrodi, especially diet, breeding behavior, sex ratio and habitat structure.