Species description

Care, breeding and tankmates

Fish profile

Temperament

Semi-aggressive

They have a very peaceful, somewhat timid, and distinctly schooling temperament, relying on numbers for safety. They must be kept in groups of at least six individuals, though groups of ten or more are highly recommended to reduce stress. When kept in large numbers, they display fascinating shoaling behaviors and their best, most vibrant colors.

Diet

Omnivore

They are undemanding micro-predators that will readily accept a wide variety of small, high-quality aquarium foods. Their diet should consist of crushed high-quality flakes, micro-pellets, and small frozen or live foods like daphnia and baby brine shrimp. Offering a varied diet ensures they maintain their best coloration and optimal health.

Sex ratio

Group

Females are generally noticeably rounder and slightly larger, especially when they are actively carrying eggs. Males tend to be slimmer, more streamlined, and often display slightly more intense coloration during spawning displays. They should always be kept in a group of at least six, where a natural mix of sexes will occur.

Feeding frequency

Twice daily

Feeding them one to two times daily with small amounts they can consume in a few minutes is ideal. Because they have small stomachs, multiple small feedings are better than one large, heavy feeding. Care must be taken not to overfeed, as uneaten food will quickly foul the water.

Bioload

The Flag Tetra produces a very small bioload due to its diminutive size and relatively light diet. A group of these small fish will barely impact the biofilter of a properly cycled, adequately sized aquarium. Standard, well-maintained biological filtration and regular, modest water changes are perfectly sufficient for their needs.

Flow

Stagnant

They originate from slow-moving streams and flooded forest areas in the Amazon basin, preferring very gentle water flow. Strong currents should be strictly avoided as they will exhaust these small fish and cause severe stress. Gentle filtration, such as from a sponge filter or baffled hang-on-back filter, is highly recommended.

Reproduction

Oviparous

They are egg-scatterers that provide absolutely no parental care to their eggs or newly hatched fry. Breeding requires a separate, dimly lit tank with very soft, acidic water and fine-leaved plants or a spawning mop. The adults will eagerly eat their own eggs and must be removed immediately after a successful spawning event.

Compatibility & tankmates

They are exceedingly peaceful and make superb additions to planted community aquariums featuring other small, calm species. Excellent tank mates include small rasboras, Corydoras catfish, Otocinclus, and peaceful dwarf cichlids. They should never be housed with large, aggressive, or highly active fish that might intimidate or eat them.

Tank level

Middle/Bottom

They are active schooling fish that primarily occupy the middle to upper levels of the water column. They appreciate an aquarium with dense vegetation around the perimeter but plenty of open swimming space in the center. Floating plants are highly beneficial as they provide shade and make these shy fish feel more secure.