Black Widow Tetra
Gymnocorymbus ternetzi

Black Widow Tetra is backordered and will ship as soon as it is back in stock.
Overnight Priority Shipping
Overnight Priority Shipping
Overnight Priority Shipping
- North Island : $28.99
- South Island: $38.99
Non-Rural New Zealand Addresses Only.
Live Fish Guarantee Policy
Live Fish Guarantee Policy
We stand behind the health of every fish we ship. That’s why we offer a Live Arrival Guarantee on all orders shipped via overnight or two-day delivery.
To qualify for a refund or replacement in the rare case of a DOA (Dead on Arrival), the following conditions must be met:
- within the expected time frame (overnight or two-day service).
- unopened bag must be provided within 1 hour of delivery.
- Someone must be present to receive the package at the time of delivery.
This guarantee is void if:
- The package is delayed beyond the expected delivery time
- The shipping address is incorrect or incomplete
- The package is left outside unattended, especially in extreme weather conditions
- The bag has been opened prior to video documentation
We do not cover losses due to courier delays, missed deliveries, or improper acclimation after opening.
We care deeply about the well-being of our fish and your experience as a customer. Please refer to our Acclimation Guide and Shipping Policy for more information.
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Black Widow Tetra (Gymnocorymbus ternetzi)
The Black Widow Tetra, also known as the Black Skirt Tetra, is a hardy and eye-catching community fish known for its flowing fins and dark, smoky-grey body with distinct black vertical bars. Originally from the slow-moving rivers of South America, particularly in Paraguay, Brazil, and Bolivia, this peaceful schooling species is perfect for beginner and experienced aquarists alike.
Black Widows typically grow to about 5–6 cm, and do best when kept in groups of 6 or more in a peaceful community aquarium. They thrive in well-planted tanks with open swimming space, gentle water flow, and stable conditions. Ideal parameters include temperatures of 22–28 °C, a pH of 6.0–7.5, and soft to moderately hard water.
Feeding is easy—they readily accept high-quality flakes, micro pellets, and frozen foods such as daphnia and bloodworms. Their active schooling behavior and dramatic contrast in coloration make them a dynamic visual addition to any tropical setup.
Temperament: Peaceful
Diet: Omnivore
Colour Form: Grey & Black
Water Parameters: 22–28 °C, pH6.0–7.5
Maximum Size (cm): 6
Classification: Characidae
Minimum Tank Size (litres): 60
Origin: Paraguay, Brazil, and Bolivia
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