Tetra / Aquarium Zone · Ballina
Gymnocorymbus ternetzi
A peaceful community fish. Grows to about 5 cm and suits a tank of 100 litres or more.
The fish, up close
The Black Widow Tetra, scientifically known as Gymnocorymbus ternetzi, is a striking freshwater fish with a sleek, elongated body and a deep black colouration that contrasts beautifully with its bright red fins. The males typically have a more intense black colouration, while females may appear slightly lighter. These tetras are active swimmers and are known for their schooling behaviour, making them a popular choice for community aquariums. They prefer a well-planted tank with plenty of open swimming space.
Care guide
Use these notes to shape a setup around the fish, then speak with our team about the tank you have in mind.
Plan your setupBehaviour
These tetras are peaceful and social fish that thrive in groups of six or more individuals. They are relatively active and enjoy swimming in the middle to upper levels of the aquarium. Black Widow Tetras are known for their playful interactions within the school, and they generally get along well with other peaceful community fish.
Tank planning
Maintaining stable water parameters is crucial for the health of Black Widow Tetras. They prefer slightly acidic to neutral water with a temperature range of 24-26°C. Regular water changes and good filtration are important to keep the aquarium clean and maintain water quality. Providing plenty of hiding spots among plants or decorations will help these tetras feel secure.
Practical details
Questions
For a specific fish, current stock or a tank setup question, speak with the Aquarium Zone team before travelling.
Contact the storeAquarium Zone regularly helps customers find freshwater fish in Ballina and across the Northern Rivers. Stock changes week to week, so contact the store before visiting if you are looking for Longfin Black Widow Tetra.
Yes. Bring your tank size, current fish list, setup photos, and any water test results so the team can help with compatibility, stocking, and care advice.
Longfin Black Widow Tetra is listed with this tank recommendation: A minimum tank size of 60 litres is recommended for a small school of Black Widow Tetras. However, a larger tank of 100 litres or more is ideal for a larger group or if keeping them with other fish species. Ask in-store for advice based on your exact setup and tank mates.
Yes. Aquarium Zone serves aquarium hobbyists from Ballina, Lennox Head, Alstonville, Wollongbar, Bangalow, Byron Bay, Lismore, Evans Head, Mullumbimby, Casino and the wider Northern Rivers.
Aquarium Zone / Ballina
Looking for Longfin Black Widow Tetra? Contact us to confirm current availability and discuss whether it suits your aquarium before making the trip.
18 Southern Cross Drive
