Family Cichlidae.
To be continued…
Keeping cichlids in an aquarium.
Keeping certain species of cichlids means strictly following certain “rules of the game”, that is, creating a familiar living space for these fish in the aquarium. Many cichlids have a bad reputation: they dig up the substrate, undermine the roots of aquarium plants, bite or even kill conspecifics or other fish, and otherwise display their predatory nature. Of course, cichlids in an aquarium do not abandon the habits inherent to them in natural conditions. Among cichlids, there are those that love to dig in the substrate.
They live mainly near the rocky bottom in Lake Tanganyika. Shell-dwellers are small cichlids belonging mainly to the genera Lamprologus and Neolamprologus. They use Neothauma mollusk shells as shelters and spawning sites. In the aquarium, they need suitable shells. Different species have their own characteristics that must be considered during maintenance and breeding. A mandatory condition for introducing fish into the aquarium is at least 15-20 liters per individual.
Cichlids from different regions of Africa have different tendencies and temperaments, meaning they cannot be recommended for co-habitation. Cichlids from Lakes Malawi and Victoria get along well with each other, but severely suppress their family relatives from Lake Tanganyika. Generally speaking, keeping fish of the family Cichlidae presents certain difficulties for the beginner aquarist. The fact is that almost every specimen of fish in this family has a unique character, the nuances of which the aquarist must catch and anticipate possible options for intervention in the tank in cases of undesirable vivid individual character traits in certain specimens. Juvenile cichlids grow in simple schools with situational leaders; often immature males and females live in separate schools in different areas of the body of water.
Maturing males and females, in competition with fish of their own sex, determine their position and hierarchical step in the school. Thus, sexually mature individuals form a more complex hierarchical school with a permanent arrangement of fish at different levels. Strong, large, brightly colored males choose the best females, which corresponds to the progress of the species as a whole. During this pre-spawning period, cichlids move to the next stage of relations: a pair of fish (in some species, still only males without a female) occupies a certain territory — a revier — and protects it from rivals. A family-territorial group is formed, and complex territorial relations arise between such groups.
As a rule, males of most African cichlid species exhibit territorial behavior to one degree or another and, when the volume of the artificial body of water is insufficient, pronounced aggression, primarily toward representatives of their own species, and secondarily toward fish of other species. When choosing a direction of activity (choosing specific cichlid species or groups of species), you need to approach the issues of aquarium volume and configuration with extreme care. Fry and juveniles of African cichlids behave quite tolerably with almost all fish of other families of approximately equal size. With too obvious a size difference, fish tend to engage in cannibalism, and in some cases, schooling harassment of smaller fish, regardless of species.
Vegetarians from Lakes Malawi and Tanganyika require a special discussion, as the aggressiveness of their males sometimes surpasses the wildest assumptions. Sometimes individual males of this type are so aggressive that they cannot fit into any aquarium of reasonable size without relentlessly destroying their rivals and sometimes the fair half of the fish kingdom. Of course, such cases are isolated, but by no means unique. Most species of African cichlids require the presence of at least two males, one of which will be dominant (head of the school), and the rest subdominants (courtiers, rivals waiting for their turn).
If stocking density standards are not met in the aquarium, the probability of subdominant individuals dying due to the aggressiveness of the dominant male increases. Three females can keep the dominant busy with enough work so that he does not distract his attention with additional bursts of aggression toward other species. No species of Central American cichlids is suitable for a multi-species aquarium. They should not be kept together with cichlids from the Amazon, whose behavior and water quality requirements are completely different. Some can be kept with cichlids inhabiting the waters of the northwestern part of South America.
The aggressiveness of the dominant is somewhat reduced by the presence of a sufficient number of shelters where subordinates can hide if necessary. It is very important that shelters are located along the entire height of the aquarium from the bottom to the very water surface, which allows territories to be divided to some extent by “floors”. If the aquarium size is minimal, shelters should be located along the entire back wall at some distance from it (5-8 cm), allowing fish to maneuver freely, moving from floor to floor. And if your aquarium resembles a quarry, this will be the rightest solution.
Yet, it would be good to fully utilize the height of the tank and place the stones so that they reach the very edges. This is the only condition under which fish will stay in the upper water layers. Plants, of course, enliven the general appearance of the aquarium and, besides, ensure water quality, and yet they should not be there. If you still decide to landscape the aquarium, choose only hard and hardy plants. It is good to divide the territory with separate protruding rock areas. Do not use sharp stones that can injure the fish.
Lighting in the aquarium should be selected not too bright, but rather subdued. If there are no plants in the aquarium, the substrate layer can be small, up to 3 cm; if there are plants, the substrate layer should be higher and depends on the plants you are going to plant. The best substrate fraction for river and lake African cichlids, except for fish from Lake Tanganyika, should be considered gravel or crushed rocks 2-7 mm in size. For Tanganyikan cichlids, coarse sand with a layer of 1 cm, with a fraction of up to 2 mm — the natural material of the bottom of Lake Tanganyika — is more suitable. Shell-dwellers and many small Lamprologus need the finest fraction of sand. Coarser sand is absolutely necessary for cichlids of the genera Enantiopus, Xenotilapia, etc., which sift it through a special gill apparatus, thereby obtaining small invertebrates.
Spawning for some rare Tanganyikan cichlid species requires a thicker layer of sand, as in their natural habitat they build crater-like nests up to 40 cm in diameter and up to 10 cm deep. However, such cichlids are usually kept in pairs in large containers without other neighbors. An important point for all digging cichlids is the rounding of the substrate, otherwise the fish can get hurt on sharp edges, and this must be remembered!
The water temperature in which cichlids are kept is one of the significant factors affecting their coloration and size, offspring quality, and reproductive capacity. The temperature regime of the water bodies where these fish live varies. In the Great African Lakes Malawi, Tanganyika, and Victoria, the temperature is highly stable, being maintained in Lakes Malawi and Victoria at 26°C, and Lake Tanganyika at 25°C. River cichlids inhabit water with a wider temperature range of 22-30°C. Therefore, river species adapt much easier to conditions with unstable temperatures, prolonged overheating, and water cooling.
It has been noted that cichlids tolerate abnormally low temperatures much easier and recover faster than after elevated ones. A temperature of 24-26°C is suitable for almost all fish. At lower temperatures, the growth of juveniles slows down first, and the period of their sexual maturation increases.
Under low-temperature conditions, cichlids do not fully acquire their peerless coloration with age, and subsequent temperature increases do not restore the color. Temporary summer increases with good water aeration are tolerated normally by fish. Among cichlids, only discus fish have elevated water temperature requirements. Their range is 28-30°C, and in case of illness — up to 35°C. Here, constant heating is indispensable. Angelfish are also heat-loving, although not to the same extent as discus fish.
The presence of a sufficient amount of dissolved oxygen in the water plays a special role in keeping African cichlids. The fact is that dissolved oxygen is the most fundamental factor for the growth, development, and reproduction of cichlids and is of much greater importance than other water chemistry indicators. It is oxygen deficiency that leads to the most tangible troubles in keeping cichlids: diseases, poor growth, refusal to eat and reproduce, and ultimately death.
Regular water changes are the second guarantee, after aeration, of cichlids’ good mood. The frequency of changes depends on many indicators — feeding density, aquarium volume, number of fish, and their size. Regarding the chemical composition of water, most cichlids are unpretentious, despite the fact that in nature fish inhabit various types of water, ranging from almost distilled, like Amazonian inhabitants, to brackish, where Asian Etroplus and some Madagascar cichlids live. One should not exactly replicate the chemical composition of lake water in the aquarium. Especially since it is still far from identical values, as data from various regions are very ambiguous. Unnecessary (or unskilled) manipulations with the chemical composition of water can lead to sharp shifts in critical parameters. And this can lead, at a minimum, to a deterioration in the fish’s well-being.
The pH value of water is one of the most important water quality indicators. Almost all lake species are adapted to normal existence only within a narrow range of pH values. Cichlids of the Great African Lakes, as well as inhabitants of large Central American lakes, feel best in slightly alkaline water with a pH of 7.5-8.5. Main attention should be paid to the pH indicator, which under no circumstances should drop to the “acidic” side (not less than 7.5). General hardness of approximately 10-12 degrees quite meets the needs of most cichlid species. Neglecting this factor can lead to mass mortality of cichlids in the shortest possible time, which sometimes happens during their long-distance transportation.
African river species easily withstand water acidification below 7.0, but still feel better in alkaline water. Inhabitants of the Amazon and Orinoco basins, as well as rivers of the western coast of equatorial Africa, prefer slightly acidic water with a pH of 5.5-6.5. Biofilters, in addition to filtering water from mechanical suspension, help partially solve the issue of completing the nitrogen cycle in the aquarium — converting organic compounds into nitrates, which in reasonable quantities are not toxic to underwater inhabitants.
It is also widely known that the water of African lakes is distinguished by particular transparency and purity. Therefore, the role of filtration in the aquarium is decisive. A system with a capacity of at least 3-5 aquarium water volumes per hour should be chosen. In this case, the necessary regime will be ensured even with intensive fish feeding and maximum stocking density for a given aquarium. Excessive current at the filter outlet can be dampened by directing the jet toward the back glass of the aquarium, using a spray bar downwards, or along the water surface. A standard internal power head with a porous sponge attachment works just as well as an external filter, but since the filter area is small, the filter material has to be washed much more often. In any case, it must be remembered that having any water filtration system does not relieve the aquarist from regular water changes!
Feeding fish in the aquarium poses no problem. In accordance with the usual division of animals into predators, vegetarians, omnivores, and parasites, cichlids have a full range of specializations by feeding methods. There are predators that steal fry or eggs of other fish species, including cichlids. Carnivores include cichlids that feed on zooplankton (daphnia, cyclops, insect larvae, freshwater shrimp, crabs). These include most African cichlids, American Acaras, Cichlasoma, and Asian Etroplus. The latter, however, do not disdain algae either.
The basis of the diet of the Tanganyikan deep-water beauty Cyphotilapia consists of mollusks. Many other mollusk-eaters are also known among cichlids. The most popular Malawian cichlids of the Mbuna group, whose name can be translated from the local dialect as rock-scrapers, are vegetarians. Omnivorous fish feed equally on plant and animal food depending on its availability. Plant food can be an important and useful supplement. Feeding adult fish can be limited to dry foods.
Features of keeping African cichlids in captivity.
Family Cichlidae. Classification of African cichlids. 
