Edit Petitella rhodostoma

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Name

Scientific name

Petitella rhodostoma

Described by

Bracketed

Family

Characidae

Summary

The rummy-nose tetra, Hemigrammus rhodostomus, is a characin from blackwater rivers of the Rio Orinoco and lower Amazon basin in Venezuela …

Size and aquarium

Maximum size

50mm, standard length

Tank size

Not recorded

Water

Temperature and pH

Temperature 24–27°C, pH 5.5–7

Hardness

2–15dGH

Conductivity

Not recorded

Behaviour

Temperament

Peaceful

Community suitability

Not recorded

Where it lives

Countries

Not recorded

Supporting text

Etymology

Petitella Géry & Boutière 1964, from the French –ella, a diminutive connoting endearment; in honor of zoologist-anatomist Georges Petit (1892-1973). rhodostomu…

Distribution

Rio Orinoco and the lower Amazon basin in Venezuela and Brazil.

Habitat

Blackwater rivers and tributaries. The water in these biotopes is typically stained brown with tannins from decaying organic material and is very acidic as a r…

Aquarium size

This is a species that should be maintained in groups numbering 10 or preferably more, and its active swimming nature requires a tank length of 36 inches/90 cm…

Maintenance

A biotope setup would be very simple to arrange. Use a substrate of river sand and add a few driftwood branches (if you can't find driftwood of the desired sha…

Water conditions

Temperature: 24 – 27 °C75 – 81 °F pH: 5.5-7.0. Its colours will become faded if kept in alkaline conditions. Hardness: 2-15°H

Diet

Omnivorous and will accept just about anything offered. It does have a small mouth, though, so correspondingly-sized foods are best. Feed a mixture of dried fl…

Behaviour and compatibility

It's a very peaceful species that won't compete well with very boisterous or much larger tankmates. Ideally, keep it with other South American species, such as…

Sexual dimorphism

Mature females are noticeably rounder in the body than males.

Reproduction

Can be bred in a similar way to other species in the genus. You'll need to set up a separate tank if you want to raise decent numbers of fry. Something around …

Can be bred in a similar way to other species in the genus. You'll need to set up a separate tank if you want to raise decent numbers of fry. Something around 18" x 10" x 10" in size is fine. This should be very dimly lit and contain clumps of fine-leaved plants such as java moss or spawning mops, to give the fish somewhere to deposit their eggs. Alternatively, you could cover the base of the tank with some kind of mesh. This should be of a large enough grade so that the eggs can fall through it, but small enough so that the adults cannot reach them. The water should be soft and acidic in the range pH 5.5-6.5, gH 1-5, with a temperature of around 26.5 – 29 °C80 – 84 °F. Filtering the water through peat is useful, as is the use of RO water. A small air-powered sponge filter bubbling away very gently is all that is needed in terms of filtration.

It can be spawned in a group, with half a dozen specimens of each sex being a good number. Condition these with plenty of small live foods and spawning should not present too many problems.

Alternatively, it can be spawned in pairs. Under this technique, the fish are conditioned in male and female groups in separate tanks. When the females are noticeably full of eggs and the males are displaying their best colours, select the fattest female and best-coloured male and transfer them to the spawning tank. Contrary to much that has been written this species spawns exclusively in the evening

In either situation, the adults will eat the eggs given the chance and should be removed as soon as eggs are noticed. These will hatch in 24-36 hours, with the fry becoming free swimming a 3-4 days later. They should be fed on an infusoria-type food for the first few days, until they are large enough to accept microworm or brine shrimp nauplii. The eggs and fry are light sensitive in the early stages of life and the tank should be kept in darkness if possible.

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Where does this come from?

My own experienceFor example, I've kept twelve in a planted 60 cm tank since March 2024.A website I sawFor example, an IUCN Red List assessment, a museum catalogue or a FishBase page.A paperFor example, Marshall et al. (2011), Water temperature differences in interfluvial palm swamp habitats of Paracheirodon axelrodi and P. simulans.A book, or something not onlineFor example, Tappin (2010), Rainbowfishes: their care and keeping in captivity.Something already on the profileFor example, the Behaviour and compatibility section already says this.

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DOI

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Authors

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Year

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Pages

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Notes

This is the 'real' rummy-nose. The species most often sold as such is, in fact, the firehead tetra, H. bleheri. These 2 are very similar in appearance, as is t…

References

3 on this profile

Name

Scientific name

Described by

Family

Summary

Size and aquarium

Maximum size

Tank size

Water

Temperature and pH

Hardness

Conductivity

Behaviour

Temperament

Social needs

Community suitability

Where it lives

Countries

Supporting text

Etymology

Distribution

Habitat

Aquarium size

Maintenance

Water conditions

Diet

Behaviour and compatibility

Sexual dimorphism

Reproduction

Notes

References

References