Max Size: 6cm

Red Laser Tetra (Hemigrammus coeruleus)

Red Laser Tetras can be pretty difficult to find. As a result, these Tetras are rare and are a highly sought after species of Tetra. These fish are one of the larger sized Tetras available in the aquarium hobby. The Red Laser Tetras friendly and active disposition and ease of care make them ideal members of a community aquarium.

Red Laser Tetras are a schooling species in nature; therefore, you should keep them in a group of at least six individuals, preferably more. Keeping these fish in more significant numbers will not only make your aquarium look more effective, but the fish will also fare much better when kept with its own kind.

Ideal tankmates for these tetras would be Danios, Rasboras, other Tetras, Pencilfish and Livebearers, as well as peaceful bottom-dwelling species such as Corydoras Catfish or smaller Loricariids. You can also keep Red Lazer Tetras with Gouramis and Dwarf Cichlids. However, it would be better to avoid aggressive or much larger species such as Angelfish as they may see these Tetras as a snack.

The best aquarium setup for the Red Lazer Tetras would be a biotope setup using river sand as a substrate and adding a few driftwood branches and twisted roots. In addition, adding some dried beech or oak leaves would complete the natural feel. It would be beneficial for your fish if you allowed the wood and leaves to stain the water a brown colour, removing decaying leaves and replacing them every few weeks, so they do not rot and foul the water. Red Lazer Tetras will also appreciate some cover from aquatic plants.

Both male and female Red Laser Tetras have transparent bodies that display a neon pink line down their sides. In addition, all their fins are transparent except for the anal and pelvic fins that are clear with white tips. However, when these fish are in spawning condition, the male's bodies will become a deep ruby red, and their fins get really dark, so much so that you could mistake them for an entirely different species altogether.


Red Laser Tetra
Quick Facts
Scientific NameHemigrammus coeruleus
Other NamesWatermelon Tetra, Coreulean Pink Tetra
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asGroups 6+
Lifespan2 - 4 years
Water Parameters
Water TypeFreshwater
PH5.5 - 7.5
GH2 - 15
75 - 82℉
23.9 - 27.8℃


In the home aquarium, the Red Laser Tetra will readily accept most good quality dried foods such as granules, flakes and sinking pellets. These modern food products have been developed to provide all adequate nutrition to maintain your fish's health and dietary requirements.

Providing additional foodstuffs such as live, frozen, and freeze-dried meals such as bloodworm, daphnia, and tubifex once or twice a week will provide additional benefits to your fish's health and well-being but is not a must for this fish.

It should be noted that bloodworms should only be given as an occasional treat and should not be used as the staple diet as they are difficult for fish to digest and can potentially cause blockages.

This fish is an omnivore in the wild, meaning it will consume some vegetable matter. Although most modern fish foods take this into account and include them in their products, you can still supplement your fish's diet with blanched vegetables such as spinach, broccoli, and zucchini. Ensure you do not overfeed your fish and remove any leftovers the following day.

Sexual Dimorphism

It is somewhat challenging to distinguish between male and female Red Laser Tetras as they look very similar. However, when they start spawning, everything changes, and the difference becomes apparent. The female will become noticeably larger as she is full of eggs, but the most fascinating change is the fact that the male transforms into a completely different looking fish. His entire body becomes bright red, and his fins turn a dark, almost black colour.

Other Tetras of interest

Adonis Tetra(Lepidarchus adonis)
African Moon Tetra(Bathyaethiops caudomaculatus)
African Red Eyed Tetra(Arnoldichthys spilopterus)
Arowana Tetra(Gnathocharax steindachneri)
Black Darter Tetra(Poecilocharax weitzmani)
Black Line Tetra(Hyphessobrycon scholzei)
View all Tetras
Date Added: 10/09/2021 14:58:14 - Updated: 02/12/2021 17:35:18