Genus Apistogramma

Apistogramma species are probably the best-known of all dwarf cichlids. While many aquarists have never seen a live Apistogramma, their photos exhibit a mystique and charisma that captures the imagination. However, with more than 400 different varieties that come from all over South America, it’s hard to know how to approach the genus. My advice is to read a lot, pick a species and begin the journey to “apisto addiction”. Keep reading for my brief guide to the genus Apistogramma.

If you are interested in a specific species you can jump directly to our Apistogramma species profiles list

Introduction to Apistogramma

The species in the genus Apistogramma are among the best-known and widely kept dwarf cichlids. The number of Apistogramma species is huge and constantly growing. There are more than 400 known species, forms, and identifiable populations. They are distributed across South America and are found in rivers, streams, creeks, ditches, potholes, ponds, lagoons, lakes, and almost every other type of habitat. They are found in blackwater, whitewater, and clearwater environments which have a significant range of pH and hardness values.

While there are many different Apistos, they all share some things in common. They almost all show significant sexual dimorphism with males generally being larger and more colorful. While in some species males and females look more closely alike, most species are highly dimorphic. All Apistogrammas are small for cichlids. In the largest species, males may occasionally approach 4″ TL but most species rarely exceed 2 ½ – 3 inches and some are quite a bit smaller.

Essential articles about Apistogramma

Keep reading for complete information about Apistogrammas. After you’ve read this article you’ll find a lot of additional specific detailed information about the genus in these “Essential Articles”.

Guide to Apistogramma Aquarium Care – This article discusses all aspects of aquarium care. Tank selection, aquascaping, water conditions, foods and feeding, tankmates, and much more are discussed in this article.

Breeding Apistogramma and other dwarf cichlids – An extensive discussion of Apistogramma spawning in the home aquarium.

Understanding Apistogramma Classification and Naming – With over 400 known species, varieties, and forms Apistos can be hard to understand. This guide can help you better understand how species are organized within the genus.

History of the Genus

While several Apistogramma species have a confusing naming history, the genus itself is pretty straightforward.

1862 – Icthyologist Albert Günther erected the genus Mesops and named the species taeniatus. Thus, the first Apistodescription was Mesops taeniatus (Apistogramma taeniatus today). Subsequently, the genus Mesops was ruled invalid and species within it were moved into Biotodoma. In the years that followed, additional species were placed into Biotodoma, Mesops, and Geophagus.

1906 – Charles Tate Reagan erected the genus Heterogramma for all the species that had been described as Biotodoma, Mesops, and Geophagus. There was no controversy about this move which helped bring organization to the naming of South American cichlids. Unfortunately, it turned out that Hetrogramma was already in use for a genus of beetle. This left the genus with an invalid name.

1913 – Charles Tate Reagan changed the name of the genus from Heterogramma to Apistogramma and the name has remained the same since.

Organizing the species

With many hundreds of species and forms of Apistogramma, the genus has been divided into groups of related species. Since they vary significantly in body shape, coloration, size, and geographic distribution, having the ability to assign species to groups makes identification easier. (However, if you are dealing with wild fish exact identification may be impossible.) I’ve written a separate article about How to Classify and Identify Apistogramma Species which is a thorough, but brief, introduction to the topic with links for those who want to know more.

No matter how expert you become at identifying Apistogramma species, you will never be able to positively identify many species without knowing the exact location where they were collected. Recent genetic analysis shows that many of what we have always considered as species are actually groups of closely related but different species. Many look exactly alike so the only way to really know what they are is to know the exact collection location.

Apistogramma agassizii is probably the best example of this. For decades everyone knew what an agassizii was and many different geographic or color forms were recognized. It turns out that all of those forms were probably separate species. Only future studies will tell, but it’s possible that the agassizii-like species found in many different rivers are all different species. So far there have not been enough genetic studies for confirmation but it appears that most of these similar-looking Apistogramma are actually different species.

This all means little to the average hobbyist who is looking for an aquarium fish. The commercial strains of A. agassizii, A. cacatuoides, A. macmasteri, and others are likely to be a mix of multiple species However, for most fish keepers it doesn’t matter. They are great fish that breed true and are always accepted as what they are known as. Seeking fish with exact identities will always be important to serious specialists but for the average hobbyist, my advice is to just enjoy your fish.

Apistogramma in the wild

The native range for Apistogramma covers all of the Amazon basin as well as the Rio Orinoco, Río Paraguay, and Rio Uruguay. These waters stretch geographically from the Ande Mountains in the west to the Atlantic Ocean in the east and from 10° north of the Equator to 30° south, a distance of more than 2,500 miles. I don’t know exactly but my estimates are that the total range of the genus could approach 4,000,000 sq miles.

With a range that large, the genus occupies pretty much any type of water source from tiny to huge and from still to moderate currents. I’m not going to discuss all the different water type possibilities here. You can research individual species to find out what specific type of habitat they come from.

Apistogramma Water Types

Since Apistogramma are found in such a diversity of locations it’s natural that they are found in a wide variety of water conditions. Depending on the species water values can be markedly different. Although soft and acidic is the general rule, some species originate in much more neutral water and I try to provide water parameters in each Apistogramma species profile. Generally, the waters that Apistos are found in are classified as one of three types.

Blackwater

Blackwater is typically found in areas of dense forest where decaying vegetation leaches tannins into the water. These waters have virtually no measurable mineral content so vegetative decay and tannin production reduce the pH, sometimes significantly. In some blackwater environments, the pH will measure as low as 3.5. Blackwater is named for its clear dark-colored water which is stained dark by the tannins. The intensity of the dark color varies and the water can be anything from the color of weak tea to strong black tea. Many blackwater Apistos can be difficult to keep because of the water conditions they require. They often need very soft and acidic water for successful reproduction and some require these conditions to stay healthy.

Clearwater

True to its name, Clearwater is usually clear but it might be tinted slightly depending on the habitat. Clearwater is usually low in dissolved solids and minerals (soft) and only slightly acidic with a pH of around 6.5. This differs from blackwater which typically has much lower pH values. Clearwater rivers are generally found toward the eastern end of the Amazon Basin and many different Apistogramma species are found in Clearwater. They are often more tolerant of a range of water conditions in an aquarium.

Whitewater

High levels of suspended sediments in whitewater rivers make the water look cloudy with a caramel-like color that is generally fairly light but varies in shade. Whitewater generally has a neutral pH of 6.5 – 7.0 and has more minerals and conductivity than blackwater or clearwater. Most whitewater rivers originate in the Ande mountains in the west and southwest portions of the Amazon basin. However, whitewater is found in a few other places. Species originating in whitewater are generally more tolerant of water parameters. To clear up any confusion, whitewater refers only to the color of the water and doesn’t refer to rapids.

Apistogramma native habitats

The variety of habitats that Apistogramma are found in is astounding. From tiny puddles to huge rivers, they seem to inhabit every type of habitat. Consequently, there is no typical habitat to describe. However, most reports indicate that habitat complexity is preferred (hiding places) and sandy bottoms are the norm. Habitat complexity is most often created by terrestrial vegetation that ends up in the water. While true aquatic vegetation is unusual, plants on the shoreline growing into the water are common. Fallen branches create woody debris piles while a layer of leaves commonly blankets the bottom. These are all materials that need to be considered when establishing an Apistogramma aquarium.

Almost all we know about habitat conditions comes from collectors and researchers who are working in low water conditions. The Amazon and its tributaries experience huge annual changes in water flows that dramatically impact water levels. When the river rises tens of feet and entire forests flood it becomes very difficult to observe or capture wild Apistos. Consequently, almost everything we know about many species is based on low-water observations and it’s likely that their habits and habitats are different in flood conditions. A stream that is nothing more than a string of connected puddles at low water suddenly becomes hundreds of square miles of habitat. Annual flooding is variable from year-to-year and helps to explain why some Apistogramma species are common one year and then seem to disappear after that. The low and high water seasons are also why the life span of an Apisto in the wild is usually quite short.

Most Apistogramma waters are in dim to dark environments. Often they are in overgrown streams in dense rainforests. where very little sunlight penetrates the water and sometimes it seems dark at midday. This is important to remember in the aquarium and avoid harsh bright light. Either use low-lumen bulbs or, my preferred method is to use plants in the tank to screen and reduce the light. Often fish raised in dark environments will develop more intense colors. Although most Apistos come from poorly lit conditions, there are some that come from waters that are exposed to full sun.

Most collectors report they are found in places with sandy bottoms. Apistogramma are “earth-eaters” and they spend a lot of time grabbing mouthfuls of sand which they slowly sift out of their gills. While they do this they can remove any tiny food particles that may be in the sand. The sandy bottoms are often partially covered by a layer of fallen leaves or detritus. They are almost always found in shallow water, usually less than a foot but sometimes deeper.

Apistogramma in the home aquarium

Since I’ve written an in-depth article about Apistogramma aquarium care that you should read, the following is only a brief overview.

You’ll want to modify your aquarium depending on what Apisto species you are keeping but these aspects of Apistogramma aquarium care can be considered universal.

• A sandy bottom is preferred – In the wild most Apistos are found over soft bottoms, usually sand. They are evolved to sift sand seeking out food items and sand in the aquarium is very beneficial.
• Complex habitats work best – A complex habitat is one that has a lot of structure that creates breaks in the sightlines and provides cover to the fish. Complexity can be created with rocks, driftwood, live or artificial plants, and is most often a combination of these. Complexity is critical if you have aggressive fish as you need to create areas that a dominant fish can’t see when patrolling his/her normal territory.
• Soft, acidic water – The majority of Apistogramma species come from water that is soft to extremely soft and acid to extremely acid (pH 3.5 – 6.5). While some blackwater species may require extreme water conditions, most Apistos can be kept in soft water with a pH of about 6.0.
• Frequent water changes – The more often you provide water changes the happier your fish will be. While they will survive on minimal water changes (20% every 2 weeks) more frequent and larger changes can make a remarkable difference. 40% water changes at least every week is my recommendation.
• Reduced light intensity – Depending on your setup, reduce the intensity of your lighting or use live plants to screen most of the light.
• A varied diet of high-quality food – Apistogramma are omnivores in nature that will eat any available food, plant, or animal. Most often it’s small insects and crustaceans along with bits of plant material and general detritus. This makes it easy for us to provide a healthy diet in our aquariums. Live, frozen and dry foods are all good options. All aspects of Apistogramma food and feeding are detailed in the Apistogramma Aquarium Care article.
• Proper selection of tankmates – How you combine your Apistos with other fish will have a big impact on how well your aquarium works out. The right combination can make an amazing display while the wrong combination can lead to chaos or even death for the fish and lots of anxiety for the fishkeeper. There is a lot of discussion of this in our discussion of Selecting Apistogramma Tankmates

Aquarium care of Apistogrammas is a broad topic with lots of considerations. I’ve only described a few factors in this overview of the genus and the Apistogramma Aquarium Care article covers all aspects in detail.

Breeding Apistogramma

I’ve written a detailed Guide to Breeding Apistogrammas which covers all aspects of breeding and rearing and if you are interested in this topic you really should read that paper.

Apistogramma are cave spawners where females typically tend the eggs and fry. In some cases, males may take a role in guarding the fry but this is not universal. They exhibit a host of different family structures ranging from a male-female pair to a dominant male with multiple females. Some species are more casual in their relationships than others. Some form tight pair bonds while in others there is no bonding that lasts beyond the current spawn.

Spawning generally takes place in a cave or some other dark and secluded location. The spawning takes 20 – 40 minutes or so and 40 – 200 eggs are laid. after spawning the male normally ignores the cave and eggs. The female tends the eggs which begin to hatch into larval fry after about 3 days. After another 5 – 7 days the fry will develop into free-swimming babies. At this point, the female leads them around the tank searching for food. Sometimes the male will join in with fry care which continues for a variable length of time. A well-fed female will spawn again quite quickly and she is unable to tend both eggs and fry.

Rearing Apistogramma fry

A potentially perplexing problem with many Apistogramma species is having entire broods turn out to be predominately male or female. Skewed sex ratios have been documented for decades, causing much anguish for fish keepers. Dr. Uwe Römer has researched this and reports that a primary determiner of sex is the temperature at which newborn fry are raised. His experiments demonstrated that the first 6 weeks are most critical with warmer temperatures producing more males and cooler temps more females. The “break-even” point is about 78°F and spawns at this temp should produce a balanced sex ratio. Unfortunately, as with everything else, this is not a hard rule and I’ve had many broods turn out 90 – 100% of one sex when my tank is at 78°. Skewed sex ratios are a problem that can hit at any time.

You won’t know if you have a sex ratio problem until the fry reach 4 – 5 months of age when they should be showing sexual differences. Raising them to this point is usually pretty easy providing they survive the first few weeks. Live foods are important to get good survival rates. Apistos can take brine newly hatched brine shrimp as their first meal and can easily handle microworms and similar tiny live foods. They can be gradually conditioned to take dried foods and, unless there are predators, they are usually pretty easy to raise. Plenty of water changes and frequent small feedings produce the best results.

Buying Apistogrammas

The first thing to know is that you will never be able to purchase some of the Apistogrammas you see photos of on the web. Browsing online will show you some unbelievable species and it’s easy to make a wish list but, most hobbyists will never have access to many of these species. There are a number of reasons for this and some of the main factors are:

• Many species are only known from photos taken on private collecting trips.
• Many species are from geographic locations where there is no tropical fish trade.
• They may come from places so remote that transport to shipping facilities is impossible.
• Their population might be so small that collecting enough for export is impractical.
• They may come from places where the government bans ornamental fish trade.
• Within every wild population there is tremendous variability in coloration and the most colorful are usually selected for photos While the species may be available, the colors you see in a photo may be far different from what you can acquire.
• Most North American hobbyists will not pay premium prices for rare species. Consequently, the rarest and most colorful species are usually sent to countries that will pay much higher prices.
• Some species appear in the hobby and after a few years vanish and, for a variety of reasons, never return.
• Some species may be extinct from habitat changes. For example, some Rio Xingu species have not been seen since the completion of a major dam flooded their habitat.

While you won’t have access to every species you find on the web, Apistogramma species are becoming more common in pet stores and many of the best independent stores regularly stock them. However, it’s an unusual store that stocks more than a couple of species. A few species have become relatively common and most stores can order them for you.

Many hobbyists today choose to purchase from a specialty fish seller or breeder online. This is a safe and proven method of buying dwarf cichlids and I’ve prepared a separate guide on Where and How to Buy Apistogramma.