Lake Malawi—a long, narrow, deep lake—lies within east Africa’s rift valley, where hundreds of endemic cichlid species have evolved to take advantage of the various biotopes available. Many of the cichlids that make excellent aquarium fish generally fall into two categories. The larger, relatively peaceful, haplochromines that are sand-dwelling or open-water feeders treasure their aquarium space. On the other hand, a large number of the remarkably colorful, smaller, boisterous, rock-dwelling cichlids called mbuna would be ideal for our ultimate African cichlid biotope aquarium.
In the wild, various mbuna species live together in crowded colonies over rocky outcrops, feeding mainly on algae that contain a wealth of small living creatures. Colorful male mbuna aggressively defend a patch of rock from other males of their own species while trying to attract passing females to spawn. In the lake, beaten mbuna males can just swim away to fight another day, while in the enclosed space of the aquarium, they are not afforded this luxury and could be killed.
Pseudotropheus saulosi. Photo by Iggy Tavares
One way to reduce aggression in the aquarium is to keep several species of mbuna cichlids in relatively crowded conditions, somewhat similar to that in the wild, so that a dominant male bully cannot continually pick on a single individual. However, each mbuna species is best maintained with just one male and three or four female fish, thus distributing the male’s attention. The number of cichlid species that you can keep together depends on aquarium size, with just three species (of three fish each) in a 55-gallon aquarium, five species in 75 gallons and six species in 100 gallons. Choice is governed by available home space and budgets.
Aquarium Furnishings and Equipment
Ideally, the ultimate African cichlid biotope for mbuna should be a 100-gallon long aquarium (measuring 60 inches long, 18 inches wide and 24 inches tall) with a hood, where six species of mbuna males, and three to four females for each species, can spread out along the length of the aquarium, staking out small territories. Ideally, aquariums should be seated on a stand built to carry the considerable weight of water and rocks and could perhaps also accommodate some of the external equipment, foods and books. Most aquarium outlets do offer favorable deals when an aquarium and stand are purchased together.
Pseudotropheus demasoni. Photo by Iggy Tavares
Another important consideration is where to place the aquarium in your home. As the furnished 100-gallon aquarium with stand weighs some 1,000 pounds, the floor needs to be strong enough to carry that weight. Additionally, several power plug points (outlets) are needed to run the various equipment associated with the aquarium.
Attractive 3D flexible rock-design backgrounds are available for fixing inside the aquarium along the back glass panel (according to manufacturer’s instructions) to enhance the appearance of this mbuna aquarium. A cheaper alternative is to stick a paper background along the outside of the glass or even to paint the back panel black. The background encourages the fish to move toward the front of the aquarium for better viewing and it also helps to highlight their beauty.
The base of the aquarium is best furnished with washed, smooth, small-grain coral sand (approximately 50 pounds) to a depth of at least 2 inches. Sand is a good choice, as it will not trap much debris and is easily stirred up when cleaning the aquarium. The sand is overlaid with pieces of limestone rocks (approximately 200 pounds), arranged to create large enough caves for 4-inch-long mbuna to disappear into, somewhat replicating their rocky terrain in the wild. Rocks are heavy and need to be arranged carefully to create stable structures that will not tumble. This is especially important because mbuna tend to dig in the sand, and that could undermine some of the rock arrangements. Various limestone rocks are available from local fish outlets, on the Internet and at expos.
Metriaclima sp. Photo by Iggy Tavares
The water in Lake Malawi is alkaline and hard, with a pH ranging from 7.8 to 8.5 and general hardness ranging from 9 to 18 dKH. Alkaline, hard water is critical to the health and well being of Malawi cichlids. As it happens, 85 percent of tap water in the United States is hard and is usually suitable for keeping mbuna. If the tap water is soft, then the water can be hardened by adding baking soda (1 teaspoon per 5 gallons of water) or adding commercial products according to the manufacturer’s instructions. Chlorine in the tap water needs to be removed, which can be done by standing the tap water in a container for at least a couple of days before use. This will allow the chlorine to dissipate. Alternatively, commercial products are available for quick chlorine removal. The limestone rocks and coral sand used in my aquarium contain calcium carbonate, which helps to maintain pH and the hardness of the water as they slowly dissolve.
Cichlid biotope. Photo by Iggy Tavares
Lake Malawi water temperatures near the surface, where many mbuna are found, range between 74 to 82 degrees Fahrenheit, depending on the season. In captivity, 77 degrees is a good base line to maintain. This is best done using two heater thermostats, one at each end of the aquarium. Aquarium water temperature can be monitored daily with a digital aquarium thermometer attached to the glass.
Water quality is of prime importance in the crowded mbuna aquarium, as the cichlids suffer if nitrogen wastes are high. Two external canister filters that provide mechanical, biological and chemical filtration with a combined flow rate of some 400 gallons per hour should be able to maintain water quality in a crowded 100-gallon cichlid tank. Separate baskets in the filter box carry different components, making it easy to clean the filter foam or filter floss pad that provides the mechanical filtration or to change the carbon filter bags that provides the chemical filtration. Bio-filter balls provide the huge surface area for the bacteria that use up the toxic nitrogenous wastes. Having two canister filters is helpful, as it allows for alternate servicing of the filtration units once a month. Cleaning the filters results in loss of some of the beneficial bacteria from sponges in particular, but these build up within a few days.
This aquarium is set up with rock and plants so that the cichlids have plenty of places to hide. Photo by Iggy Tavares
Canister filter inlets are usually arranged to pick up the aquarium water at the bottom of the tank and return the water to the top of the aquarium, creating a nice current of water around the tank that the mbuna enjoy. One of the outlets could be fitted with a spray bar that increases aeration at the water surface.
Lighting in this mbuna aquarium is needed to show off the mbuna in their best colors rather than to promote plant growth. This can be done with a pair of T5 fluorescent tubes with accompanying ballasts fitted in the aquarium hood. A good choice for the mbuna aquarium are 50/50 fluorescent tubes, as they provide a combination of full-spectrum daylight and actinic blue light. This lighting tends to enhance the coloration of the blue mbuna, while yellow mbuna also look good, as does the pale-colored limestone rockwork. Other tube combinations that provide natural daylight or tropical light with some red hue can also be used according to personal tastes. Another option is LED lighting where cost of the pendants are high, but the lamps are reputed to last several years without any performance loss and electrical running costs are also much lower.
Mbuna require high-quality, hard-alkaline water that is low in nitrogenous waste products to remain healthy. In the aquarium, fish excrete ammonia, which is rather toxic; it damages their gills, causes stress and weakens the fish’s immune system. In an established aquarium with a healthy filtration system, naturally occurring colonies of Nitrosomonas bacteria convert ammonia to nitrite, which is further converted to nitrate by Nitrobacter. Nitrate that cannot be broken down further has to be removed by weekly, 20 percent water changes.
A newly established aquarium system does not initially have the required bacterial colony, which builds up as fish are introduced and fed in the aquarium. One way of speeding up the beneficial bacteria colonization is to pick up a cupful of live sand from a healthy aquarium at the fish outlet or from a friend’s aquarium to add to the new aquarium substrate. Better still, add used bio-filter balls to the new canister filter media. Before the addition of any mbuna, this friendly bacterial colonization can be sped up by using a product containing ammonium chloride, which releases ammonia. Make sure to use the product according to the manufacturer’s instructions.
Test the water regularly for ammonia and nitrites, especially when starting out, so that evasive action, such as partial water changes, can be done as necessary. During water changes, the substrate should be stirred to remove any buildup of detritus. The inside front glass will need regular wiping down to keep it spotless for unimpeded viewing of the beautiful cichlids.
Mbuna cichlids belong to several genera, including the generally mild-mannered Labidochromis spp. and the aggressive Melanochromis spp. Species within other genera do show varying amounts of aggression, while individual cichlids could act differently in a particular aquarium depending on circumstances. The often-available Melanochromis auratus and Maylandia lombardoi are particularly colorful when young, but they should be avoided in this aquarium because of their aggressive nature.
Setting up the ultimate African cichlid biotope for mbuna does take time and effort, and it costs hundreds of dollars for equipment, furnishings and colorful cichlids. Photo by Iggy Tavares
Colorful, monomorphic species—where male and female display virtually the same fabulous adult coloration—are rather desirable. Yellow labs (Labidochromis caeruleus) that have a delightful yellow body, powder-blue cichlids (Pseudotropheus socolofi) and the black-and-blue striped Maingano (Melanochromis cyaneorhabdos) are all monomorphic and relatively mild-mannered while offering contrasting colors and shapes, making these three species a suitable selection for a 55-gallon mbuna tank and beyond.
For a 75-gallon aquarium, you could add two more species. A relatively mild-mannered, small cichlid is the dimorphic orange-back mbuna (Cynotilapia zebroides), also called “cobue,” with black-barred males and blue females. Another option is the rusty cichlid (Lodotropheus sprengerae). Males have brownish-yellow faces with lavender purple bodies. Females are less bright.
For the 100-gallon aquarium, you could choose one more species, such as the red zebra (Metriaclima estherae), where wild-type females have a stunning red-orange body and males are blue or orange (aquarium strains); the monomorphic Pseudotropheus spp., also called “acei,” with male and female fish having blue bodies with striking yellow fins; or Metriaclima spp., also called “elongates,” offering a whole number of species, with both sexes showing a barring pattern.
Other suitable species are P. demasoni, a diminutive monimorphic, blue-barred mbuna; P. saulosi, which has blue-barred males and bright-yellow females; and L. chisumulae with navy-blue/ white-bared males and pearly white females. These species suggestions are offered as a guide, with final selections depending on what is available in your fish store location.
Once the aquarium has been cycled and beneficial bacteria have started to get established in the canister filters and substrate, building up the mbuna community can start—but it does take time and should be accomplished over a few months. One way is to add one species of mbuna at a time, starting with a relatively docile species and adding the more aggressive species last. Buying subadults or juveniles is cheaper, and they settle into an aquarium setup more readily. The disadvantage is that it is not always possible to tell the sexes apart in young fish, especially when males and females of the selected species show similar coloration in adulthood. With subadults, look out for dominant fish among the group and for egg spots on the anal fin to help distinguish young male fish. Ask the store manager’s help when selecting the fish. Explain that if you buy a group of seven mbuna, you would like to bring back two or three fish. Hopefully, the manager will agree to exchange them for you. Ensure that all the fish in the tank are healthy looking and not hollow-bellied. They should be active and feeding well before your purchase.
A good mbuna to begin with is the yellow lab. As they get acclimated, feed these mbuna sparingly for the first few days. This will allow the filtration system time to kick in and build up the beneficial bacterial colony for breakdown of nitrogenous waste. Use test kits to check the water for nitrogenous wastes, and perform partial water changes if the ammonia levels start to spike. As your cichlids grow over the following weeks, keep a lookout for excessive aggression. Your goal is to keep just one male with three or four females and remove (and return) the extra males.
After a month, even if no extra yellow lab males have been removed, you can add the next species of seven or so young mbuna, perhaps the powder blue cichlids, and proceed with growing them on and returning extra unwanted male fish. You could go as far as adding the third species of mbuna a few weeks later before removing extra males, but then this will have to be done before adding the fourth group of cichlids. Using two nets does make it a little easier to carefully catch particular fish, but removing some of the rock work would help. Some seven or eight months down the line, the aquarium should be filling up nicely as the number of mbuna species reaches full complement and the cichlids grow in size. By then, there should be just one adult male per species group. Hopefully, the male cichlids, which are aggressive by nature, should not be causing too much trouble. However, situations could arise that might require the removal of a particularly unruly male cichlid for a week or two, as they tend to chase other males. Removal of an aggressive male allows others to come to the fore. Having lost status, on reintroduction, hopefully the returning male will be less unruly. Reintroduction could be done in darkness at night.
Healthy, mature mbuna spawn readily in the aquarium. Male mbuna that have staked out a territory continually try to entice passing female mbuna of their species while fending off other males. This takes the form of fin flaring and body shivering. When ready to breed, the female follows the male to his site, where they circle one another, and after a few practice runs, the female starts laying an egg or two at each half turn. During spawning, male and female go around in a circle, with female laying eggs, followed by her picking up eggs and then picking up sperm deposited by the male to fertilize the eggs. This procedure can take up to an hour, with the pair breaking off occasionally to chase away intruding fish. When egg laying is complete, the mouth-brooding female with eggs in her buccal cavity takes refuge in a neutral part off the tank.
Initial incubations might be aborted after a few days with the female starting to eat again. This could be because the brood wasn’t viable or because she just wasn’t able to endure starving any longer, as she is unable to feed while incubating eggs in her mouth. However, if she is not too harassed or hungry, the female will start carrying the developing fry in her mouth to full term, which lasts about 18 to 24 days. By then, fry measure almost a half inch total length and are fully developed, miniature replicas of their mother and display her coloration. First spawns can be as low as 10, but as the females grow, fry number can increase to 30 or more. The mouth-brooding female has to release the fry so that they, and she, can feed.
Keep in mind that other adult mbuna in the community aquarium consider the fry as food. Some fry might survive in the smaller crevices among the rocks and grow on to maturity. To raise a good number of fry, the mouth-brooding female could be removed on day 16 to a separate small aquarium, where the released fry will grow rapidly on crushed mbuna foods. Healthy, mature female mbuna spawn regularly, as often as every six to eight weeks!
Setting up the ultimate African cichlid biotope for mbuna does take time and effort, and it costs hundreds of dollars for equipment, furnishings and colorful cichlids. However, there is always something interesting to observe in this aquarium, especially as the colorful mbuna spend most of their time out in the open, providing hours of entertainment every day. Moreover, with just a little regular care and attention, this biotope aquarium should provide years of interest and pleasure as mbuna can live for more than 5 years as long as their needs are met. It is well worth the effort.
Iggy Tavares started keeping fish more than 50 years ago when he caught some wild guppies in an African stream. As cichlids are his passion, he thoroughly enjoyed a recent visit to Lake Tanganyika—a hot bed of cichlid diversity. He is an enthusiastic fish photographer and enjoys writing about his numerous experiences around the world.