Rummy-nose Tetra

Hemigrammus rhodostomus

The tightest-schooling tetra in the hobby, with a red nose that fades when stressed.

Water

Freshwater

Temperature

75–82°F

pH

5.5–7

Hardness

2–12 dGH

Max size

2 in

Min tank

20 gal

Temperament

Peaceful

Social

Schooling (8+)

Swim level

Middle

Diet

Omnivore

Care level

Intermediate

Lifespan

5-6 years

Breeding

Egg-scatterer

Suitability

Common

Origin

Lower Amazon

The bright red head is also a water-quality gauge — it pales when conditions slip. Rummy-noses school more cohesively than almost any other fish, making a big group mesmerizing.