Apistogramma agassizii

photo of Apistogramma agassizii Rio Mariera pair with fry

Apistogramma agassizii (A 234 – A 243) is one of the best-known and most widely kept of all Apistogrammas. There are many different color forms/varieties in the wild and several colorful domestic strains are available. They are easy to care for and are usually great for a single-species or community aquarium.

Introduction to Apistogramma agassizii

Apistogramma agassizii has long been a popular aquarium fish. This was an article from the magazine Aquatic Life published in March 1919

Apistogramma agassizii was first described in 1875 from specimens collected in 1865 & 1866 by Professor J. L. R. Agassiz. They were first imported into Germany in about 1909 and have remained available in the hobby ever since

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Historically, they are one of the few Apistogramma species that’s been correctly identified by hobbyists. Most Apistos discovered before the 1970s were kept and distributed under multiple different names (this still continues to some extent today). However, since it was first described, A. agassizii has typically been properly identified. This is probably due to the distinctively banded, spade-shaped tail. Unfortunately, our certainty of identification is being challenged by new genetic testing and analysis (see more below).

A. agassizii is the species upon which both the A. Agassizii Group and A. Agassizii Complex are based. Apistogramma agassizii are found throughout the Amazon basin and have the largest geographic distribution of any Apistogramma species. They are found in a wide variety of habitat types and water conditions. As might be expected of a fish with such a wide distribution, there are many different color forms found in nature.

Photo of Apistogramma agassizii cf. Rio Madiera
This pair of Apistogramma agassizii cf. Rio Madiera has formed an excellent bond and each parent helps to care for their newly hatched fry

Identifying A. agassizii

Agassizii are quite dimorphic with males being larger and more colorful than females which makes them easy to sex. They are slightly elongated with a low and even dorsal fin. They typically have a dark lateral band that runs from in front of the eye to the beginning of the tail. Males have distinctive spade-shaped caudal fins (tail) that have 3-4 alternating dark and light bands from the edge to the center. The shape and color of these bands will vary between strains and individuals.

Photo of Apistogramma agassizii female
This is a typical A. agassizii female in fairly neutral color. After spawning she will turn bright yellow.

Non-breeding female A. agassizii are typically a dull color that can range from gray to brown to dusky yellow until they put on their brood colors. Then they become a vibrant yellow with a very contrasting black pattern that may appear as a stripe or as a single spot on their side.

Aquarium care and breeding of A. agassizii

We try to provide aquarium conditions that match the native waters of our fish. However, A. agassizii originate from waters with a wide range of pH and hardness values. Therefore, unless you have specific collecting information, it’s best to provide water that should be good for all areas. This means a pH of 5.5 – 6.5 and hardness <4 dGH (soft). Many will thrive in water that varies from this and the domestic strains can handle water that strays even further. However, they are not hard water fish.

They prefer a sand substrate with a complex habitat that features multiple cave areas as well as tangles and thickets of plants, leaves, or other materials. In a well-designed tank, they’re usually not too aggressive to tankmates but they don’t do well with more than one male A. agassizii in a tank. A single male with several females can work as long as there is plenty of cover.

photo of Apistogramma agassizii female with young fry
        This female A.agassizii is caring for her 2-day-old fry. The black markings on the side of the female can change rapidly and combined with fin motions and swimming posture allows her to clearly communicate with her brood and other apistos.

Breeding is the same as with most Apistos. The female will select a spawning location – usually a cave. When she is ready she entices the male to join her and begins to lay her eggs. The male enters the cave periodically to release his milt and fertilize the eggs. After spawning is complete the female takes sole responsibility for guarding the eggs. In 2 – 3 days the eggs hatch and she will guard the newly hatched larval fry until they become free-swimming after another week or so.

The fry will feed on newly hatched brine shrimp, micro worms, or other tiny live foods. In a well-established aquarium, they will graze on any hard surface to feed on the microscopic life. They don’t readily take prepared foods but will pick at particles of food the mother ejects through her gills. As they grow they become easier to feed and they will grow pretty quickly with good water changes.

For detailed information about Apistogramma care and breeding read these additional articles:

Apistogramma and Dwarf Cichlid Aquarium Care

Breeding Apistogrammas and Other Dwarf Cichlids

Apistogramma agassizii in the wild

A. agassizii have the largest geographical range of all Apistos. They are found along almost the entire length of the Amazon and well into the tributary rivers. Mike Wise describes their distribution as “the Rio Negro, Rio Madeira/Purus of Brazil, the Río Amazonas of Peru and Colombia, and the Brazilian Solimðes/Amazon/Rio Tocantins as far east as Belem, plus coastal streams along the Atlantic near the Amazon Delta.” This is a truly massive area.

As expected with such a large range, they have been collected in all types of water conditions. Most of the reports I’ve seen fall between pH 5.0 – 6.5 with a hardness of <1 – 4 dGH. These are conditions that are easy to replicate in the aquarium. Sandy substrates and complex habitats are preferred.

How many wild A. agassizii-type species are there?

Classification of A. agassizii is always changing and you can find the latest info in these two excellent resources by Mike Wise:
A description of Apistogramma species-groups
Apistogramma Species List by Species-Groups/Complexes

With such a huge range, it’s no surprise that many wild strains have been identified and named by hobbyists and collectors. There has been much debate about whether they are all one species or are they many species and recent genetic studies have shown that there are many different species closely related to A. agassizii. In fact, each major river drainage may have its own species. This has everyone wondering how to address wild agassizii-type fish.

photo of male A. agassizii "Red Tail" or "Red Black"

Unless you have a verified collection location for your fish it’s impossible to tell exactly what they are. For decades, hobbyists have treated the different forms as all being A. agassizii, thus, most fish in the hobby are a mixture of various species. However, some exporters are now providing wild fish with collection location information which can allow breeders to maintain “pure” strains from these locations.

What to do if you have fish called A. agassizii? I recommend you treat them as domestic aquarium fish and pay no attention to them being anything other than agassizii. Don’t worry about cross-breeding because there is no way of knowing what you are crossing. However, if you distribute them to others, make sure you just call them A. agassizii and don’t add any sort of geographic name.

Apistogramma agassizii domestic strains

In addition to the multitude of wild forms, there has been a lot of selective breeding of Apistogramma agassizii in the hobby and some very colorful aquarium strains have been developed. While A. agassizii are sold under many names, two primary strains are usually available from online sellers and quality pet stores.

Although these aquarium strains are spectacular, wild Apistogramma agassizii have a beauty of their own, and if you ever have a chance to acquire wild fish I encourage you to do so. If you acquire a wild strain and have a reliable collection locality you should take care to keep the strain pure.

A. agassizii “Double Red”

The most popular aquarium strain is usually called “Double Red” but its also commonly sold as “Red Tail”, “Red-Black”, “Double Full Red”, “Super Red”, “Blue-Red”, “Red-Gold” and many other names. They are beautiful fish and very popular. They tolerate a range of water conditions and eagerly eat most foods. In a tank with a complex habitat they are not overly aggressive making them a good “first Apisto” for hobbyists.

Photo of Apistogramma agassizii "Red Tail" also called "Double Red"
Adult male Apistogramma agassizii “Red Tail” – this aquarium strain has been developed through many generations of captive breeding. Variations of this strain are sold under many different names.

A. agassizii “Fire Red”

The “Fire Red” variety is a strikingly colored fish with body colors ranging in shades of brilliant yellow. Their spectacular body colors are topped by a purple/maroon stripe extending along the top of the body. Their tails are a vibrant red color and some have a white band outlining the tail. I’ve found them easy to breed and care for. However, it’s very difficult to tell the sex of juveniles and sneaker males are a real problem.

Photo of Apistogramma agassizii "Fire Red" pair
Male and female pair of A. agassizii “Fire Red”. This domestic strain is quite popular and often available.

Where to buy Apistogramma agassizii

A. agassizii are commonly available and you shouldn’t have much trouble finding them. However, if you are looking for a specific strain it might take some searching. The domestic strains are commonly available and many good pet stores try to keep them in stock. Ask your favorite shop if they can order them for you.

Most online Apisto dealers offer A. agassizii on a regular basis. They will often have both domestic and wild strains and you might even find several wild strains offered at the same time. Visit Where to Buy Apistogrammas and Other Dwarf Cichlids for more information.