A large, incredibly colorful, and highly aggressive South American cichlid. Known for their striking metallic green/blue scales and vibrant orange or white tail margins. As their name suggests, they are highly territorial and require very careful tankmate selection, usually only coexisting with other large, robust cichlids or armored catfish in very large tanks.
At a Glance
Tank Requirements
Water Parameters
Temperament & Compatibility
Available Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Male
Adult males grow significantly larger, develop a prominent nuchal hump (forehead bulge) as they mature, and display the brightest colors. They are fiercely territorial and usually intolerant of other male cichlids.
Differs in 3 traits from base species
Also known as: Adult Male, Bull
Female
Females remain smaller than males, lack the prominent nuchal hump, and are slightly less colorful. However, they are still highly aggressive, especially when paired up and breeding.
Differs in 4 traits from base species
Also known as: Adult Female
Juvenile (Grow-out)
Sold at smaller sizes in most pet stores. While they may seem manageable in community tanks as juveniles, they grow rapidly and will begin bullying or eating smaller fish as they mature. Requires a massive tank upgrade.
Differs in 5 traits from base species
Also known as: Baby, Juvenile
Green Terror Care Guide Summary
The Green Terror, scientifically known as Andinoacara rivulatus, belongs to the Cichlids - South American family group. Adults reach a maximum size of approximately 25 cm and have a compressed body shape with a moderate growth rate. Classified as aggressive, this species primarily occupies the mid-level and bottom zones of the aquarium and produces a high level of biological waste.
To thrive, the Green Terror requires a freshwater only aquarium with a minimum volume of 200 litres and a tank length of at least 120 cm. Water temperature should be maintained between 20°C and 28°C, with a pH range of 6.5–8 and a general hardness of 5–20 dGH. A moderate water flow is preferred.
Due to its specialist needs, the Green Terror is best suited for fishkeepers who can provide a carefully planned setup. This species is available in 3 varieties: Male, Female, and Juvenile (Grow-out). Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.
Green Terror Habitat Setup
When setting up an aquarium for the Green Terror, a moderate water flow best suits their natural preferences. Because this species occupies the mid-level and bottom zones, the aquarium layout should prioritise open swimming space in the centre of the tank for free movement and sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include a sand substrate to accommodate their sifting behaviour, smooth gravel or rounded substrate to protect their sensitive barbels, and driftwood, which can serve as both a hiding place and a dietary supplement. Keepers should note that expect substrate disturbance, so lightweight décor should be secured and live planted layouts may be difficult to maintain, as this species tends to uproot or consume vegetation.
Green Terror Compatibility Notes
Classified as aggressive, the Green Terror is adaptable and can be kept singly or in a small group, offering flexibility when planning a community tank. When choosing tankmates, any fish small enough to fit in its mouth will likely be eaten, conspecific aggression can be intense, especially in smaller tanks, and territorial behaviour may cause issues if hiding spots or floor space are limited. Selecting tankmates that favour different water layers from the mid-level and bottom zones can help reduce competition and territorial overlap.
Frequently Asked Questions About Green Terror
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