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Maximum size : 6 cm

Red Laser Tetra - Hemigrammus coeruleus : Complete Fish Profile & Care Guide

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Red Laser Tetras (Hemigrammus coeruleus) are a highly sought-after species in the aquarium hobby due to their rarity. These larger-sized Tetras possess a friendly and active disposition, making them perfect for community aquariums. Keeping them in groups of at least six individuals, as they are a schooling species, will not only enhance the aesthetics of your aquarium but also help them thrive.

Red Laser Tetras are compatible with a variety of tankmates, such as Danios, Rasboras, other Tetras, Pencilfish, Livebearers, and peaceful bottom-dwelling species like Corydoras Catfish or smaller Loricariids. They can also coexist with Gouramis and Dwarf Cichlids, but avoiding larger or more aggressive species such as Angelfish is better. 

The best aquarium setup for Red Laser Tetras is a biotope setup with river sand as the substrate, driftwood branches, twisted roots, and dried beech or oak leaves. These tetras appreciate cover from aquatic plants and stained water from the wood and leaves.

Both male and female Red Laser Tetras have transparent bodies, displaying a neon pink line down their sides, with transparent fins except for the clear anal and pelvic fins with white tips. During spawning, the male's body turns into a deep ruby red, and its fins get darker, giving them a striking appearance.

Red Laser Tetra Photos

Sexual Dimorphism

Differentiating between male and female Red Laser Tetras can be challenging due to their similarities. However, during the spawning period, distinguishing between the two sexes becomes relatively easy. Females become visibly larger due to the abundance of eggs in their body. The most notable transformation is observed in males, whose entire body becomes a vibrant shade of red, and their fins turn almost black, rendering them entirely distinct from females.

Quick Facts

Scientific NameHemigrammus coeruleus
Year Described1908
Other NamesWatermelon Tetra, Coreulean Pink Tetra
Max Size6 cm
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asGroups 6+
LifespanUp to 5 Years

Water Parameters

Water TypeFreshwater
PH5.5 - 7.5
GH2 - 15
75 - 82
23 - 27

Natural habitat

Red Laser Tetras hail from the lower Rio Negro River Basin in Peru, South America, and information on their natural habitat is scarce. Their habitat is believed to comprise of sandy and silt substrate, accompanied by bogwood branches and sparse vegetation. These fish inhabit soft, tannin-stained water areas that are shrouded in shade, adding to the intrigue of their natural environment.

How to breed the Red Laser Tetra

Regrettably, there is a scarcity of information available on breeding the Red Laser Tetras. However, they are likely to follow a similar breeding pattern to other species within the Hemigrammus genus.

You will require a separate breeding tank equipped with dim lighting and very soft, warm water to breed Red Laser Tetras. The tank should be heavily planted with fine-leaved vegetation such as java moss, and spawning mops can also be used as an alternative. To condition your fish for breeding, it is recommended that you feed them with plenty of live and frozen foods to encourage spawning. 

You can identify a female that is ready to spawn by her plump appearance. At this point, you should introduce your best-coloured male and largest female into the breeding tank. Once the pair is ready to spawn, the male will begin to swim energetically around the female, performing a courtship display where he flicks his fins and shimmies near her. When ready, the female will discharge her eggs, and the male will fertilise them.

On average, a single spawning can produce around 100 to 150 eggs. However, the parents will not provide any parental care and will consume the eggs if given the opportunity. Therefore, removing them from the tank immediately after spawning has finished is crucial. The eggs are sensitive to light, so it is advisable to keep the breeding tank in darkness. 

Typically, the eggs hatch within 24 to 36 hours, and the fry will become free-swimming a few days later. To begin with, you should feed the fry with infusoria or paramecium before gradually introducing finely crushed flake food. After a few days, you can provide them with newly hatched baby brine shrimp and micro worms to aid their development.


Diet & feeding

Red Laser Tetras are not particularly picky eaters and will consume a range of foods, including high-quality dried food like crushed flakes and micro pellets, as well as live, frozen, and freeze-dried foods like brine shrimp, daphnia, and mosquito larvae. However, it is important to note that these Tetras are not scavengers and will not consume any food that falls to the bottom of the tank. Thus, it is crucial to avoid overfeeding to prevent water pollution.

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