True Rummy-Nose Tetra

Hemigrammus rhodostomus

The *Hemigrammus rhodostomus* is the 'True' Rummy-Nose Tetra, often confused in the aquarium trade with the almost identical and more widespread *H. bleheri* (the common Rummy-nose) and the *Petitella georgiae* (False Rummy-nose). It is distinguished from the Bleheri by the red coloration of the snout which is strictly confined to the head and DOES NOT extend beyond the gills, and by the presence of a faint dark line running along the caudal peduncle until it merges with the spectacular black and white zebra stripes of the caudal fin. Slightly larger than the Bleheri (up to 5-6 cm / 2.5 inches) and with a more silvery body, it is a tireless pelagic swimmer and one of the most cohesive and spectacular schooling fish that can be hosted in large South American aquariums.

Family: Characidae
Origin: Sud America (Bacino inferiore del Rio delle Amazzoni e fiume Orinoco in Venezuela e Brasile)
Tank use: Used in 0 tanks

Temperature

24 °C - 28 °C

5 - 7

Water type

Freshwater

Tank level

Zona media e inferiore. A differenza dei Neon che stazionano o si nascondono, i Testa Rossa pattugliano instancabilmente in lungo e in largo il terzo inferiore della colonna d'acqua.

Adult size

6 cm

Description

Perfect and Tireless Schooling Effect:

If you dream of those perfect aquariums with a huge swarm of identical fish turning all together exactly at the same time like in an oceanic documentary, these are the fish you must buy. They are the only freshwater species that maintains a military group swim for life even without the threat of real predators.

Care and observations

The Visual Alarm (The Faded Snout):

If you want to know if the aquarium filter is about to collapse or if you forgot a water change, look at your Rummy-noses. They are the fire alarm of fishkeeping. If the water is perfect and the nitrates are at zero, their snout will be a blinding ruby red. If the snout suddenly becomes faded, pink or dull grey, you have a pollution spike in progress: stop feeding and change the water, or they will die within two days.

Not in Short Aquariums (Compulsive Swimmers):

Unlike Neon Tetras that stay still among the plants, Rummy-noses are race cars on a highway. They never stop. They swim back and forth all day in perfect compact formation (Schooling). If you put them in small or short 60-liter (15-gallon) aquariums, they will literally go crazy hitting the opposite glass or stop swimming, becoming apathetic. The tank must be no less than one linear meter (3 feet) long.

How to Know If You Were Scammed in the Store (True vs Common):

90% of the time in the store they will sell you the *H. bleheri* (Common Rummy-nose). How do you recognize the TRUE *rhodostomus*? Look at where the blood on the face ends. In the true *Rhodostomus*, the bright red stops exactly at the eye and the gills like a mask, and does not go further. In the commercial *Bleheri*, the red "dribbles" in a confused way going down past the gills to stain almost half of the belly.

Fish profile

Temperament: Puro pacifico, perennemente in movimento sincrono. Non è mai aggressivo verso altre specie né all'interno del proprio branco.
Diet: Onnivoro. Accetta avidamente cibo secco di alta qualità, ma i colori del muso e i contrasti della coda esplodono solo se integrati quotidianamente con artemia salina viva o congelata, dafnie e micro-chironomus. Le loro bocche sono piccole, necessitano di granulati fini affondanti (1 mm).
Tank level: Zona media e inferiore. A differenza dei Neon che stazionano o si nascondono, i Testa Rossa pattugliano instancabilmente in lungo e in largo il terzo inferiore della colonna d'acqua.
Minimum group: 10
Adult size: 6 cm
Minimum tank: 120 L
GH: 1 dGH - 10 dGH
KH: n/a
TDS: n/a
Conductivity: n/a
Sex ratio: Branco stretto obbligatorio (più sono, migliore è l'effetto visivo del loro nuoto, minimo 10). Le femmine adulte sono molto più tozze e gravide (rotonde) rispetto ai maschi spiccatamente affusolati a forma di siluro.
Feeding frequency: 1-2 volte al giorno in dosi distribuite per tutta la lunghezza della vasca, per evitare risse alimentari nel branco in movimento.
Bioload: Medio-Basso
Flow: Corrente da Moderata a Forte. Sono eccellenti nuotatori e amano contrastare il flusso in formazione.
Reproduction: Dispersori di uova 'in campo aperto'. Molto complessa da indurre in cattività senza una preparazione chimica certosina. Richiedono acqua estremamente tenera e acida (Torbata, pH sotto 6.0) e luce quasi inesistente, poiché le uova sono molto sensibili all'attacco fungino in acque dure.
Compatibility: I 'Dither fish' perfetti per eccellenza per grandi acquari amazzonici. Data la loro taglia adulta (6 cm), sono gli unici Caracidi sufficientemente grandi (se inseriti adulti) e veloci da poter convivere tranquillamente in enormi vasche dedicate agli Scalari (Pterophyllum altum) e perfetti con pesci di fondo pacifici come Corydoras e Geophagus.

Image gallery

Licensed images linked to the species or, when marked, to the closest representative taxon.