The Andinoacara rivulatus, more commonly referred to as the green terror, is unmistakably recognizable by its green scales, vivid orange stripes, and distinctive nuchal hump. Despite its intimidating name, which suggests it is an aggressive freshwater species, this fish often startles aquarium enthusiasts.
Here, we’ve created a guide based on extensive research of all things cichlids to show you all of the wonderful aspects of the green terror cichlid and how to care for it.
Article Summary
- Despite its intimidating name, green terror cichlids are relatively easy to care for in terms of aquarium needs and diet, but they can be aggressive in a community tank.
- Green terror cichlids have teeth at the front of their mouths, which they use for predation and defense.
- Tank setup should include natural barriers like driftwood and large flat stones, as well as a sandy substrate and low-light conditions.
What is a green terror?
The green terror cichlid (Andinoacara rivulatus), also referred to as white saum or gold saum, is a freshwater fish from South America that is well known for their unique coloration and patterns. They get their name from their coloration and aggressive personality, but can be an interesting addition to your aquarium. Green terrors are part of the cichlid family, but are a unique find among them.
Where are green terror cichlids from?
This freshwater fish has a native range from the Tumbes River in Peru to the Esmeraldas River Basin flowing over North-West Ecuador. A tropical fish, green terrors live in calm tropical river basins and tend to stay away from the saltier river mouths where the ocean meets the river.
Are green terror fish difficult to keep?
Despite having a fear-inducing name, this fish is relatively easy to manage when it comes to aquarium needs and diet, however in a community tank they can become very aggressive fish.
What does a green terror look like?
Aptly named, the true green terror is covered in metallic green with bright blue markings across their face and body. Mature fish have an orange stripe around their dorsal and caudal fins. Though some aquarists say that there’s more greenish yellow edging along the caudal and dorsal fins.
Green terror cichlids are ray-finned fish meaning that their fins are supported by long, bony spines under their scales. This creates a wavy pattern in their fins that is aesthetically pleasing to many aquarium owners. The dorsal fins are long, pointed and continuous, containing roughly 14 spines, and the orange line accents this feature among all the other fish in your aquarium.
Difference between male and female green terrors
Like many species the male fish tend to have brighter coloration than the females. Males also have a distinct hump (called a nuchal hump) on their forehead that is made out of fatty tissue, which is lacking from females. The purpose of this hump isn’t exactly clear, but researchers speculate that it is used for sexual selection and fat storage.
Some females also lack the orange coloration along their fins, but as this isn’t very common it isn’t a good feature to differentiate between sexes.
What does a baby green terror look like?
Young fish look similar to adults, but the juvenile fish tend to have a silver-blue hue tint to their scales. As they grow their coloring darkens into the deep, metallic green. You can expect their coloration to change sometime between 6-8 months.
How to tell the difference between blue acara and green terror?
Andinoacara rivulatus is often mistaken for the Andinoacara pulcher, otherwise known as the blue acara, due to their similar coloring. In fact, at one point in time these fish were considered the same species, though now we know about a few key differences.
| Andinoacara rivulatus (green terror) | Andinoacara pulcher (blue acara) |
| Maximum size of 12 inches Large, pronounced nuchal hump Generally more aggressive | Maximum size of 8 inches Smaller nuchal hump |
FUN FACT
“Andinoacara” is the scientific name for the Cichlidae family. Both Andinoacara rivulatus and Andinoacara pulcher are part of the cichlid family.
Do Green Terrors have teeth?
Surprisingly, yes! Green terror fish actually have two sets of teeth. Pharyngeal teeth, which are found in the back of their throats and serve a similar purpose to molars, and teeth at the front of their mouth.
Having teeth at the front of the mouth is fairly uncommon for fish, but since the green terror is a carnivore having sharp teeth at the front of the mouth can be used to rip and pull apart prey. It is also thought to be a useful defense adaptation, especially since the green terror cichlid is such a territorial fish.
As an aquarist you shouldn’t be worried about the chance of your green terror biting you when doing water changes or feeding, they are usually too scared to come close and hover near the edges of the tank.
How big do green terror cichlids get?
The size of your green terror cichlid depends on the tank size you keep it in while it grows. On average green terrors grow to be around 8 inches in captivity, but some owners have gotten theirs to grow to 10 inches by housing them in a larger tank than the 35 gallons/fish that’s recommended.
If this is your plan you should start with the maximum tank size instead of starting with a small tank and increasing tank size as your cichlid grows as this defeats the purpose of having a large tank to begin with.
In the wild, these freshwater fish are known to grow up to 12 inches.
Food & Diet
In order to ensure bright coloring, you should provide a varied diet of live, frozen, and dried food to them.
What to feed green terror?
In their natural environment the green terrors eat insects, worms, insect larva, and invertebrates. In captivity they’ve been known to consume more plant matter and vegetables, so you should provide a variety of both to have a healthy fish.
We recommend a protein-rich diet of feeder fish, pellet food, red bloodworms, brine shrimp, crickets, and with the occasional vegetable such as lettuce and spinach.
How much to feed green terror?
When feeding a green terror cichlid it is useful to refer back to the 3 minute rule. The 3 minute rule is when you allow the fish to eat as much as they want in a 3 minute span a few different times a day.
his technique is especially helpful for fish who are prone to overeat leading to digestive problems like bloating or constipation. We recommend having two 3 minute feedings per day for adult green terrors, and three 3 minute feedings per day for juveniles and fry.
What can I feed my green terror if I run out of food?
Unfortunately, if you run out of fish food there is not much you can feed to your green terror. If you do feed your green terror cichlid any human food try to keep it as close to their natural diet as possible.
Ask yourself “Would a green terror find this in South America river basins?” If the answer is yes then it is okay to feed it to them short term but pick up more suitable food ASAP! If you have to feed your green terror cichlid something because you ran out of food we recommend:
- Fish filets, chopped into small pieces
- Beef heart
- Shrimps
- Mussels
Temperament & Tankmates
Choosing the proper tank mates is perhaps the most complicated aspect of terror care. With popular smaller fish such as african cichlids out of the question, it’s hard to find tank mates that are both appealing and easy to care for.
Are Green Terrors aggressive?
Yes, they are aggressive fish and extremely territorial, in fact, their aggressiveness is where green terrors get their name. House green terrors in a spacious tank, as territory is usually the root of all aggression. By using a large tank they will have enough space, a chance to claim a small territory, and hopefully leave their other tank mates alone.
It’s important to note that the green terror cichlid is a benthopelagic fish, in other words, it doesn’t stay in one part of the water column, but will swim around the whole tank. This generally makes finding suitable tank mates tough as you can’t assume that they will stick to their individual parts of the tank and not interact.
TIP
When keeping your green terror with other fish be sure to include large tank decor. Not only will this keep your fish stimulated, but your green terror will likely choose a piece of decor to be territorial over rather than the whole tank.
Can Oscars live with Green Terror?
While both oscars and green terror cichlids can be aggressive they can be housed together and do well because they are both large fish. Here are a few of our suggestions on how to make this pairing work,
- When purchasing your green terror cichlid make sure that it is originally smaller than your oscar cichlid
- Introduce the green terror to the tank second
- If the oscar and green terror cichlid start out and grow in the tank together generally the aggression will decline over time
Ideal tank mates for green terror cichlids
Since the green terror cichlid is a fairly large fish you need to ensure that fish of similar size are kept with it in the community tank. Smaller fish will likely be eaten due to the green terror cichlids aggression and territorialism.
A male and female fish will create a bonded pair…
A male and female fish will create a bonded pair which would make them ideal tank mates for each other as there will be little to no aggression. Other good tank mates include
- Firemouth cichlids
- Jack dempsey Cichlids
- Flowerhorn Cichlids
- Silver dollar Cichlids
- Convict Cichlids
- Bristlenose pleco
- Clown pleco
- Striped raphael catfish
Tank mates to avoid
You should completely avoid placing African cichlids in a tank with green terror cichlids as they will get harassed and eaten due to their small size. Snails, crabs, and shrimps should also not be used as the green terror cichlid is notorious for eating them. When choosing tank mates keep in mind that any small fish is likely to be targeted by green terrors, as they are fairly large cichlids.
Green Terror Cichlid Care
Care for these vibrantly colored fish is fairly easy and is similar to most cichlid care.
Tank Size
In order to reduce as much aggression as possible the tank needs to be as spacious as possible to encourage exploring and enrichment.
What Size Aquarium Do Green Terrors Need?
To keep a bonded pair of green terror cichlids you need a minimum of 66 gallons, though a tank of 75 gallons would be preferable. Generally, you should avoid keeping more than two fish at a time as they are not schooling fish and far too territorial to keep a large amount in a tank.
NOTE
Green terrors can also be kept as single fish, and do not need other green terrors.
How Many Can Be Kept Per Gallon?
The absolute minimum tank size for one green terror is 35 gallons, however, we recommend 50 gallons to further reduce aggression and ensure that it is growing properly.
Green Terror Tank Conditions
| Water Parameters | |
| Water Temperature | Can range between 68-80, but ideally between 72-77 |
| pH | 6.5-8.0 |
| Water Hardness | 5-20 dGH |
RECOMMENDATION
While the pH has a fairly large range we recommend keeping your tank as close to a neutral pH as possible. Generally, these fish tend to stay away from river mouths because of the slightly acidic nature of saltwater.
Green Terror Tank Setup
When planning out your tank you should design it with the activity levels and curiosity of green terrors in mind. Since they like to swim throughout the whole water column your green terrors will need a variety of different objects to explore. Green terrors prefer low light conditions, and enjoy having natural barriers like driftwood or large flat stones to claim as their territory.
Tank decor
We recommend using a sandy substrate to cover the bottom of your cichlid tank as green terrors are known to dig. Be sure to stay away from large pieces of gravel that could cause bowel obstructions if your fish were to swallow it.
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You can place large river stones in your aquarium to give it some levels. As long as the stone is larger than the green cichlid mouth there is no danger of swallowing.
Since green terrors are known for digging, if you plan to add vegetation to your tank you should use floating plants. Plants like java ferns and anubias provide shade while also giving the feel of the natural habitat your fish live in.
Adding tank decor and live or artificial plants will give other fish the opportunity to escape green terrors if they become too aggressive.
Tank equipment
Like all tanks you should have a filter in your green cichlid tank to keep your fish healthy. Not only will a filter keep tank conditions and water parameters good, it will also provide water circulation.
Because cichlids come from a river habitat they like to have a low water flow throughout the aquarium. Be sure to choose a powerful filter as cichlids produce a lot of waste which can lower your overall water quality.
TIP
If you find your filter has a too powerful water flow, attach a sponge or a plastic water bottle cut in half to the water output. This will help soften the waterfall while still maintaining the powerful circulation.
Green Terror Cichlid Health
These large cichlids are fairly healthy and do well as long as the water quality is acceptable.
Green Terror Lifespan
Green terror cichlids live 7-10 years in captivity, making green terror cichlid care no easy feat. When deciding if this fish is for you be sure to consider the commitment you are making to be able to care for the green terror its whole life.
If you are having trouble with your green terror cichlids not living as long as expected you should first question if you are providing proper care including good water quality, diet, and stress factors. Then you should think about whether you are buying your fish from a reputable breeder.
Common Diseases
Green terror cichlids are prone to normal freshwater diseases as all freshwater fish are. Problems like freshwater ich, parasitic and bacterial infections, and skin flukes are common and can be treated using medicine from your local pet store.
Green terror cichlids are particularly susceptible to two specific diseases:
1. Head and Lateral Line Erosion (HLLE)
Often called hole in head disease, HLLE causes fish to suffer from the deterioration of the flesh. Holes and deep peaks occur in both their head and body. While no one is completely sure why this happens it is believed that high water hardness levels are the cause.
2. Lymphocystis disease
A viral infection, and commonly mistaken for ich during the early stages, lymphocystis causes the growth of white nodules on skin, gills, and fins. While it doesn’t often result in mortality, unless a severe infection, these lesions can be unappealing.
It is most often caused by inadequate water parameters, though with the improvement of water quality it usually resolves on its own. As it is spread from fish-to-fish contact if you suspect your fish might have lymphocystis we recommend removing and placing it in a separate tank.
Breeding green terror cichlids
While breeding does seem scary, green terrors tend to form bonded pairs, making the breeding process very easy.
Can you breed green terrors?
Yes, to induce green terror spawning raise the water temperature of the tank to a range of 77-88 and begin feeding live food. This mimics environmental conditions of the natural breeding season and ensures both parents have enough energy to complete the breeding process. Female green terror cichlids produce up to 600 eggs at once for the male to then fertilize.
The fish will begin showing signs of being ready to breed by cleaning the substrate and looking for nesting areas. Once spawned the female fish will lay yellow, transparent eggs on a flat rock or the bottom of the tank (she will dig through the substrate to get there!).
Watch the video below to learn more about breeding green terrors.
Are Green Terrors good parents?
Unlike most egg layers green terrors are extremely good parents and can remain in the same tank as their hatchlings. However, if you are keeping your cichlids in community tanks you should consider moving them to a breeding tank to ensure that other fish don’t eat the healthy fertilized eggs.
Eggs will take 3 to 4 days to hatch after being fertilized and another 2 to 4 days before becoming free swimmers. Like most fish species the tiny fry should be fed a diet of live food starting with infusoria and changing to baby brine shrimp when they become big enough.
Be prepared to transfer your fry into other tanks fairly fast after hatching fry and juvenile green terrors grow almost a half inch per month and will reach maturity between 2 to 4 inches.
Is the green terror for you?
If you’re looking for a tank addition that is sure to add a hint of tropical atmosphere, and flashy colors this cichlid could be for you. Green terrors are excellent fish to have alone or in addition to other tank members and are sure to compliment your aquarium’s personality.
But, if you think the Green Terror is not for you, I’d recommend the Kribensis cichlids, a peaceful and colorful species perfect for beginners.
Conclusion
After reading our guide we hope you’ve fallen in love with the Andinoacara rivulatus as much as we have. With a spicy personality and vibrant coloring this fish is sure to keep things in your aquarium interesting.