GloFish Tetra (Gymnocorymbus ternetzi)

The GloFish Tetra is a genetically modified variant of the Black Skirt Tetra (Gymnocorymbus ternetzi) that has been bioengineered to display vibrant, fluorescent colors. These brightly colored fish, which come in shades like electric green, cosmic blue, and sunburst orange, are extremely popular among aquarium enthusiasts for their striking appearance. Though they look exotic, they share similar care requirements with the standard Black Skirt Tetra, making them a manageable species for both beginners and experienced aquarists.

Origins and Genetic Modification

The GloFish Tetra is not a natural species but rather a result of genetic modification. The original species, Gymnocorymbus ternetzi, hails from South America, particularly the slow-moving rivers, streams, and floodplains of Paraguay, Argentina, and Brazil. Scientists added genes from jellyfish or coral into the DNA of these fish, giving them their fluorescent glow, which becomes more intense under blue or blacklight.

These GloFish were initially developed for scientific research to detect environmental toxins. However, they gained popularity in the aquarium trade for their eye-catching colors.

Physical Appearance

The GloFish Tetra closely resembles its ancestor, the Black Skirt Tetra, in body shape and size. They are typically about 1.5 to 2 inches (4-5 cm) long, with a flat, round body. What sets them apart, of course, is their vivid, fluorescent hues, which come in a variety of colors such as:

• Electric Green
• Starfire Red
• Cosmic Blue
• Sunburst Orange
• Galactic Purple

These colors are inherited genetically and remain vibrant throughout the fish’s life, unlike dyed or artificially colored fish.

Caring for GloFish Tetras in Aquariums

GloFish Tetras are hardy fish that adapt well to various tank conditions, making them an excellent choice for beginners. Since they are genetically modified versions of Black Skirt Tetras, they have the same care requirements.

Tank Requirements:

• Tank Size: A minimum of 10 gallons is recommended, though a larger tank (20 gallons or more) is preferable, especially when keeping a school of 6 or more.
• Water Conditions: GloFish Tetras thrive in water temperatures between 70°F and 80°F (21°C to 27°C), with a pH level ranging from 6.0 to 7.5. They prefer soft to moderately hard water.
• Lighting: Standard aquarium lighting works well for GloFish Tetras, but to enhance their fluorescence, adding a blue or blacklight can make their colors truly pop.

Diet: GloFish Tetras are omnivorous and will accept a variety of foods. To keep them healthy and vibrant, a balanced diet should include:

• High-quality tropical flakes or pellets
• Freeze-dried or frozen foods like bloodworms, brine shrimp, and daphnia
• Occasional vegetable matter like blanched spinach or spirulina flakes

Feed them 2-3 times a day, ensuring that all the food is consumed within a few minutes to prevent overfeeding and maintain water quality.

Behavior and Compatibility

GloFish Tetras are peaceful, schooling fish that should ideally be kept in groups of 6 or more. They tend to be more active and display their natural behaviors when in a group. They are generally non-aggressive and get along well with other community fish.

Tankmates: Given their peaceful nature, GloFish Tetras do well in community tanks with other similarly sized, non-aggressive species. Some good tankmates include:

• Neon Tetras
• Cardinal Tetras
• Corydoras Catfish
• Zebra Danios
• Harlequin Rasboras
• Platies
• Guppies

It’s best to avoid housing them with larger, aggressive fish such as Cichlids or Betta fish, which may nip at their fins or outcompete them for food.

Breeding GloFish Tetras

While breeding GloFish Tetras is similar to breeding Black Skirt Tetras, the company that developed these fish restricts their breeding for commercial sale. In nature, they are egg scatterers, meaning the female will release eggs into the water, and the male will fertilize them. If you are interested in breeding, ensure a separate breeding tank with fine-leaf plants or a spawning mop to protect the eggs, as the adults may eat them.

For breeding:

1. Maintain a stable water temperature around 78°F.
2. Use soft, slightly acidic water.
3. Once the eggs are laid and fertilized, remove the adults to prevent them from eating the eggs.

The GloFish Tetra (Gymnocorymbus ternetzi) is a stunning and visually captivating addition to any aquarium, offering vibrant colors that stand out under standard and specialized lighting. With their peaceful nature and ease of care, these fish are well-suited for community tanks and beginner aquarists alike. Just like their natural counterparts, they enjoy the company of their own species and other peaceful tankmates, making them a fantastic option for a lively and colorful aquarium.