Diamond Tetra

Moenkhausia pittieri

Characins

A stunning, deep-bodied tetra endemic to Lake Valencia in Venezuela. Named for the brilliant, iridescent scales on its flanks that sparkle like diamonds under the right lighting. They are highly active, peaceful schooling fish that thrive in well-planted aquariums. Males develop spectacular, flowing fins as they mature.

At a Glance

Adult Size6 cm
Body ShapeCompressed
Growth RateModerate
TemperamentPeaceful
Water TypeFreshwater Only
Flow PreferenceModerate
Waste OutputLow
StockingSchool of 6+

Tank Requirements

Minimum Volume75 L
Minimum Length60 cm
FlowModerate
Water TypeFreshwater Only
Must-Haves in the Tank
Plants - Densely coveredPlants - Floating

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Water Parameters

Temperature2428°C
pH67.5
Hardness415 dGH

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Temperament & Compatibility

Aggression LevelPeaceful
2/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least6 fish
Max per TankNo limit
Can Live Alone?No — needs a group
Behavior Traits
Hyperactive / Fast SwimmerFry Predator

Available Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Standard (Unsexed / Juvenile)

The standard commercial representation, often sold as juveniles before distinct sexual dimorphism appears. They require a school of at least 6 to feel secure and prevent fin-nipping out of stress.

Same care requirements as the base species

Also known as: Juvenile

Male

Adult males develop striking, elongated, and flowing dorsal and anal fins, and exhibit a much stronger diamond iridescence with slight violet hues. They will perform mock-battles to impress females.

Differs in 1 trait from base species

Also known as: Adult Male, Show Male

Behavior Traits
Hyperactive / Fast SwimmerFry PredatorLong Finned (Nipper Target)

Female

Females have shorter, more rounded fins and a slightly plumper, deeper body, particularly when carrying eggs. While less ornate, they still display the signature diamond sparkle.

Differs in 1 trait from base species

Also known as: Adult Female

Adult Size5.5 cm

Diamond Tetra Care Guide Summary

The Diamond Tetra, scientifically known as Moenkhausia pittieri, belongs to the Characins family group. Adults reach a maximum size of approximately 6 cm and have a compressed body shape with a moderate growth rate. Classified as peaceful, this species primarily occupies the mid-level zone of the aquarium and produces a low level of biological waste.

To thrive, the Diamond Tetra requires a freshwater only aquarium with a minimum volume of 75 litres and a tank length of at least 60 cm. Water temperature should be maintained between 24°C and 28°C, with a pH range of 67.5 and a general hardness of 415 dGH. A moderate water flow is preferred. An aquarium test kit can help you monitor these values.

The Diamond Tetra is a rewarding species to keep, provided its core environmental needs are met. This species is available in 3 varieties: Standard (Unsexed / Juvenile), Male, and Female. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.

Diamond Tetra Habitat Setup

When setting up an aquarium for the Diamond Tetra, a moderate water flow best suits their natural preferences. Because this species occupies the mid-level zone, the aquarium layout should prioritise open swimming space in the centre of the tank for free movement. Useful additions include dense planting to provide cover, break sightlines, and reduce stress and floating plants to diffuse overhead light and create shaded areas.

Diamond Tetra Compatibility Notes

Classified as peaceful, the Diamond Tetra is a schooling species that feels most secure in a sizeable group, where natural shoaling behaviour reduces stress and brings out their best colours. When choosing tankmates, their energetic swimming style may stress more sedentary or timid species. Selecting tankmates that favour different water layers from the mid-level zone can help reduce competition and territorial overlap.

Frequently Asked Questions About Diamond Tetra

How big does Diamond Tetra get?+
Diamond Tetra (Moenkhausia pittieri) typically reaches a maximum adult size of approximately 6 cm. They have a compressed body shape and a moderate growth rate.
What tank size does Diamond Tetra need?+
A minimum aquarium volume of 75 litres and a tank length of at least 60 cm are recommended for Diamond Tetra. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Diamond Tetra need?+
Diamond Tetra thrives in freshwater only conditions with a temperature range of 24–28°C, a pH between 6 and 7.5, and a general hardness of 4–15 dGH. A moderate water flow is preferred.
Is Diamond Tetra peaceful or aggressive?+
Diamond Tetra is classified as peaceful with an aggression score of 2 out of 10. They are generally well-suited to peaceful community tanks.
How many Diamond Tetra should be kept together?+
Diamond Tetra is a schooling species and should be kept in groups of at least 6. Larger groups help distribute aggression and encourage natural schooling behaviour.
Does Diamond Tetra have any special tank requirements?+
Yes. Diamond Tetra benefits from plants - densely covered and plants - floating in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.

Similar Species

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Glowlight Tetra

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Congo Tetra

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Emperor Tetra

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