The Uaru, also known as uaru amphiacanthoides, is an uncommon South American cichlid known for its distinctive triangular body shape.
They are not as brilliantly colorful or marked as other cichlids such as the Starry Night cichlid, but what they lack in color, they make up for in intelligence and character.
They are not an easy-care species. But for experienced fishkeepers, the Uaru cichlid offers a decades-long relationship with intelligent, good-natured fish that will get to know you and anticipate your presence.
Are you interested in this triangle cichlid? Read on for the key information you need to successfully care for and maintain healthy Uarus.
|Size:||8-12″ (20-30cm) in captivity, however, Uaru a. of over 14 inches have been found in the wild.|
|Tank:||75 gallons for a pair is the minimum. 125 gallons or larger is preferable.|
|Strata:||All over but tend to stay in the middle or bottom of the tank.|
|Hardness:||Soft to medium. dH range: 5-12|
|Temperature:||80 F-85 F (26 – 30 C)|
Uaru Origin and Appearance
The Uaru cichlid is native from the upper Orinoco river to the middle and lower Rio Negro in Brazil and Guyana and its tributaries. It is also common between the Rio Japurá and Rio Tapajós, along the Rio Solimoes, and the main stem of the Amazon river.
Across this wide range, they are valued not as aquarium species but as food fish. They are often netted or caught by hook and line and sold in local markets.
The name Uaru is the word for toad in one of the native Amazonian languages. Uaru amphiacanthoides has several different local names, including Chocolate cichlid, Triangle cichlid, and Waroo.
The Uaru fish is both a blackwater and whitewater species. It thrives in both very warm tannin-stained and clear flowing water. In both environments, they are found near structures such as rocks, logs, branches, and plants.
It is an omnivore fish that feeds on crustaceans, worms, insects, fruits, plant matter, and detritus.
Uarus are not commonly available at most fish stores. You can find them online from reliable wholesalers. Most Uaru you will find come from German and Indonesian commercial breeders.
In appearance, the Uaru has the classic cichlids oval or disc-shaped body. It has a row of spines embedded in its dorsal fin that when extended, gives the fish a triangular shape. The spines can deliver nasty punctures, so care should be taken if you handle your Uarus.
The anal fin also extends nearly the entire length of its body, making it a powerful swimmer.
Uarus are considered high-contrast coloration fish. Their primary and secondary colors are opposite on the color spectrum. Juvenile fish have bland, mottled patterning that resembles dead leaves. This is camouflage to help them survive from being eaten by larger fish until they are large enough not to be prey.
Mature fish have bright yellow eyes with black pupils. Their body coloring ranges from an even, subdued gray-brown to yellow with small brown blotches. A distinctive large, black mark runs the length of their lower body. This mark, along with a smaller mark at the base of their tail, can be subdued or very distinct.
During spawning, the Uaru goes into a very distinct color change. Their sides become black with some brown along the edges. Their eyes gain a red spot that looks quite fierce.
The Uaru have very small scales. Their sides appear smooth and leathery. When seen up close, you will notice that each fish has fine markings such as dots running along their lateral line and wavy lines on their gill plates. These markings are slightly different on each fish.
The average size of adult fish when well cared for is about 10 inches. In the wild, Uarus can grow to over 12 inches. Their average lifespan is 8 to 10 years.
The Uaru is one of the most mild-mannered cichlids. Uarus can have tank mates and be a part of a nice and peaceful Amazon species tank aside from when they’re feeding and breeding. That’s because they tend to become aggressive during these times.
Uaru has teeth they use to graze on vegetation and chew on wood. These teeth are prominent enough that they can bit you hard enough to draw blood.
They are very intelligent fish that are constantly exploring their environment. They quickly learn to recognize their feeders.
While Uarus are mostly herbivores, they do very well on a mix of meaty and plant food. They respond well to cichlid flakes and pellets and appreciate other treats as well.
A diet that is heavier in plant matter can have a positive effect on the color contrasts of your Uaru.
If you want to mix up your Uaru diet, here are some alternatives that are known to be well accepted.
- Live foods (live brine shrimp and small pond snails)
- Romaine lettuce
– Tank Size
Because of their size and nature, Uarus need large, planted aquariums to keep them successfully. At a minimum, a 75-gallon tank is needed to keep a young pair. You can easily go above 200 gallons if you are keeping adult fish and have a small school of Uaru if you are creating an Amazonian biome.
Large tanks are more complex than small home aquariums to keep and are not usually suited to beginning hobbyists. They require powerful filtration systems to handle that volume of water. With the cost of Uarus being anywhere from $10 to $30, a high-quality filtration system is an investment in the long-term health of your fish.
– Water Conditions
Uarus, in particular, produce more waste than other species, so it is important to conduct weekly water changes of up to 30 percent of the tank. It is not realistic to do this manually on large tanks. Clean and fill aquarium systems for large tanks are worth the investment for the time and effort they save you.
You will also need a supply of replacement water that is chemical-free, balanced, and at the right temperature for your habitat.
When cleaning your Uaru tank, you may need long-handled brushes and sponges. Uraus can be territorial and may try to nip your hands. As mentioned above, this can hurt.
Maintaining the temperature of large aquariums also requires more robust heaters and sometimes a combination of heater and heat lamp. This may be needed if you live in cooler climates or the temperature of the room where you keep your fish is constantly below 80 F.
Water quality is very important to Uraus and Amazon species. The water in their native environments tends to be clean and well oxygenated. Water levels should be kept at a pH of between 6.5 and 8. Water hardness is best at a soft to medium dH range of 5 to 12. Use test strips and weekly monitoring to ensure the water stays in this range.
Aquascaping an Uaru habitat can be fun. Working with larger spaces allows you to use larger hardscapes and other elements to create realistic or whimsical environments.
Both sand and gravel make good choices for a substrate. If you are going for a blackwater-themed tank, select dark gravel.
Assortments of large and small rocks arranged to form caves will give them places to explore. If you have juvenile fish, they may be shy and will use these caves to hide.
If you plan on keeping a small school of Uaru with the intent of them breeding, place flat rocks or slate strategically in the tank to create surfaces on which they can lay eggs. More about that in the breeding section.
Logs or bogwood are a welcome feature in an Uaru tank. Use natural wood. Your fish will graze on it and also nibble at the wood. This will help keep the growth of their teeth in check.
If you are going for a blackwater theme, you can use a blackwater conditioner or a peat bag to stain the water. In dark tanks, the Uaru’s eyes and iridescent spots along its fins will stand out nicely.
Plants are a matter of personal choice. Some hobbyists believe that Uaru will chew up any plant you place in the tank. Others think that fast-growing species will survive the grazing.
Many Uaru keepers add dried leaves to their habitat. The leaves absorb water and sink. As they deteriorate on the bottom, the Uaru will nibble on them and the algae that grow on them.
If you do choose to try them in your tank, do not use plastic or artificial plants. The Uaru will graze on them and ingest the plastic, which would clog their digestive systems. This can be fatal to your fish.
– Tank Mates
One of the best traits of Uarus is their peaceful nature. They are not live fish predators by nature and will peacefully coexist with even small species such as tetras. This gives you great flexibility in choosing tank mates for your fish.
Any warm water, peaceful fish that is not a fin nipper is a good choice, but Amazonian species are adaptable to the water conditions necessary for Uaru’s good health.
Here is a list of tank mates to consider:
Dwarf Gourami: The Dwarf Gourami is a small, colorful member of the species. These fish are peaceful schoolers and tend toward orange and red hues. Keep them in schools of 10 or more.
Pearl Gourami: The Pearl Gourami is covered with white, pearl-like markings. They are of similar temperaments and like the same types of vegetative habitats. They are an ideal choice, especially when you are kitting out an aquarium of over 30 gallons. Pearl Gourami does best in groups of 6 or so balanced heavily toward female fish.
Silver Dollars: The Silver Dollar is a species native to South America that can do well with Uaru. They are mostly peaceful, preferring the company of their species. They tend to leave other fish alone if they cannot fit them in their mouths.
Cyprinids: This family of fish contains most carp species. Its smaller members tend to live in the bottom layer of tanks and are omnivores. They mix well with other species as long as you do not overcrowd the tank.
Rosy Tetra: The Rosy Tetra, as well as many other species of Tetra, thrive in the same water conditions. They are peaceful although they may engage in fin nipping when stressed or in overcrowded tanks.
Guppy: There are many varieties of guppy that make great tank mates. What they all have in common is that they are peaceful fish that are not too small and get along well with everything that will not eat them. Some of the more ornamental varieties add splashes of color to your community tank.
Bristlenose Pleco Variants: A few different color variants will keep well together and may result in interesting-looking varieties through breeding.
Corydoras: Like Plecos, Corydoras are a variety of bottom-feeding catfish commonly placed in tropical freshwater aquariums. They grow up to 4 inches in size and are peaceful omnivores.
Cardinal Tetra: Cardinal Tetra makes great neighbors with many kinds of similarly gentle species. A small school of Cardinal Tetra adds beauty to any aquarium and does not create any type of significant bioload to the tank. Always a great choice. Add them in groups of 10.
Neon Tetra: Another great tank mate choice. Adding them in groups of 10, same as Cardinal Tetra, per 20 gallons of tank will give you an ever-moving, shimmering display.
Green Neon Tetra: If you want to keep a brightly colored aquarium, the Green Neon Tetra is another tank mate to consider. Similar in size and appearance to the Neon Tetra, the Green Neon Tetra, as its name implies, has a beautiful streak of neon green along its sides.
Here are some species best avoided as tank mates for Uaru:
Kissing Gourami: This species of Gourami is a popular aquarium fish because of the kissing motions it uses to both feed and fight. It grows quite a bit larger than the Honey Gourami, up to 12 inches in length, and while quite beautiful, it can be aggressive to smaller fish in all levels of the aquarium.
Paradise Gourami: The Paradise Gourami is a beautifully striped and colored member of the Gourami family that is known both for its appearance and aggressive behavior. They will often fight other fish to the death and should not be placed in aquariums with peaceful fish such as Bristlenose Pleco.
Other cichlids: There are many members of the cichlid species, but most of them are too aggressive to do well with Uarus. Trying to cohabitate them will lead to bullying and fighting.
Oscars: Members of the Oscar family tend to grow too large, too quickly, and have belligerent attitudes. Small Oscars will badger them, and large Oscars will eat them.
If you plan on breeding your Uarus, some forethought on tank mates will contribute to your success. Tank mates too small to eat Uaru eggs or to hassle the spawning adults are better long-term choices.
Uaru reproduction is a difficult proposition for all but the most determined keepers.
Male and female Uraus can be difficult to tell apart. The only certain way is to handle the fish and examine its vents for sex organs and risk hand punctures from their fins.
Some keepers have success by getting a grouping of at least six Uaru at a young age and raising them in a tank large enough for breeding pairs to create a territory. Hopefully, at least one of the fish will be a male or a female.
Another challenge in breeding this species is that you do not know if your fish are fertile. So many keepers and commercial houses have created species hybrids that many of the fish you buy can be sterile. If you want to breed Uaru fish, make sure you purchase from a source that will guarantee the fertility of the fish they sell.
Well-kept Uarus that are comfortable in their environment are more likely to be conducive to spawning when they reach maturity at about five or six months of age.
Indications that your Uaru may be in a breeding state start with the body and eye color changes. Your fish will become darker in color and may start to pair off.
They will find a flat rock surface and lay the eggs to be fertilized. Once that is done, the pair will take turns guarding and fanning the eggs. You may observe the male removing or eating non-viable eggs.
Sometimes the male will eat the entire clutch. This often happens with younger males spawning for the first time. Usually, after a few cycles of this, they will fan and guard the eggs so they can gestate.
Uaru eggs hatch in about five days. Once they are all out, the parents move them to a shallow nest and feed them with secretions from their skins for about a week.
Once the fry are free swimming, the parents will abandon their duties and go back to their usual routines. The fry will stay close to them to continue to feed on the skin secretions as they begin to transfer to other foods.
The Uaru fry do well on foods sized for fry, such as tiny brine shrimp, and will nibble on algae growing on wood structures in the tank.
- Uaru cichlids can be hard to find. They have limited availability.
- If you want to try breeding them, get fish from breeders who will warrant their fish or their viability.
- Uaru will grow to eight or 10 inches in captivity and can reach 13 inches in the wild.
- The species does best in large aquariums, where they have room to swim. A 75-gallon tank for a pair is a good size and 200 gallons or larger for a grouping of them.
- Uaru can be kept in tannin-stained or clear water. It depends on the overall visual appeal you want to create.
- Clean, well-balanced water is essential to their survival. Change at least 15 percent of the water weekly.
- Use test strips weekly to monitor water pH and hardness.
- Use heaters and lamps to keep the temperature between 80 F and 85 F.
- A good filtration system will help keep the water clean and the temperature of the water evenly throughout the aquarium.
- Using a sand or gravel substrate, decorate with flat stones, piles stones, driftwood, and bogwood to mimic their natural environment.
- Wood is essential in Uaru cichlid tanks. They will nibble on it and need it as part of their diet.
- Uarus are among the most peaceful cichlids and get along with other peaceful species that tolerate warm water and are not fin nippers.
- If you plan on breeding your Uaru, avoid tank mates that are egg eaters or bottom feeders.
- Signs that your Uaru may begin breeding include darkening of their coloration and a change from yellow to red in their eye colors.
- Uaru lay their eggs on flat stones and guard them after spawning. The eggs usually hatch within five days.
- For the first few weeks of their lives, Uaru fry will feed on secretions from their parent’s skin.
- Baby Uarus grows quickly and can be sexually mature in as few as five months. They can live up to 9 years.
- Uarus are primarily herbivores but will eat some meaty foods. You can mix cichlid flakes, pellets, vegetables, and small amounts of proteins to keep them healthy.
Uarus are a fish of subtle beauty that give keepers a challenging yet rewarding experience in Amazon habitat creation and maintenance.
If you can successfully breed Uaru cichlids, you will be joining a growing number of aquarists who are developing the knowledge base of a hard species that is well worth the effort.
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