Dimidiochromis

This fish grows to a rather impressive size, reaching 25 cm as an adult. The body of Dimidiochromis compressiceps is noticeably flattened laterally, making it the "flattest" cichlid in the lake. The back has rounded contours, while the ventral part is almost straight. The dorsal and anal fins are located closer to the caudal peduncle. The fish's mouth is equipped with powerful jaws studded with many sharp teeth. Males' coloration resembles metallic blue, sometimes with a slight greenish tint, and their orange fins are speckled with characteristic colored spots. Females and juveniles typically have a silvery hue.

Endemic to Lake Malawi in Africa, Dimidiochromis compressiceps is found in many areas of the lake. Its preferred habitat is shallow, open areas with sandy bottoms, where Vallisneria thickets are present. Sometimes these fish can also be found among rocky formations. They prefer calm waters with barely noticeable currents. In their natural environment, their diet consists of small fish.

The fish's behavior is characterized by moderate aggression; it does not attack other aquarium inhabitants of similar size, except for its own kind — males of the same species can engage in deadly skirmishes. The optimal keeping option is a harem, with one male for several females. It should be remembered: any smaller fish automatically becomes potential prey.

For such a large fish, an aquarium of at least 500 liters will be required. Such spacious conditions are necessary to provide Dimidiochromis with enough room to accelerate; in cramped spaces, it quickly loses vitality. The aquarium decor can be quite simple: a substrate of sand or fine gravel, supplemented by a small zone of Vallisneria thickets. It is important not to spread the vegetation over the entire area, but to group it. The quality and composition of the water are crucial for the fish's well-being. Optimal parameters are considered to be: slightly alkaline pH and medium water hardness (dH). Detailed information on parameters and methods for their correction is available in the "Hydrochemical composition of water" section. Given the large size of the fish and its carnivorous diet, a significant amount of waste is produced, leading to rapid pollution. Therefore, weekly gravel vacuuming and 20–50% water changes are necessary. The volume of water replaced depends on the tank size, fish population, and filtration system efficiency: the more productive the filter, the less water replacement will be required. The minimum equipment set must also include heating, aeration, and lighting systems.

Small fish will, of course, become prey for this impressive predator. However, in a home aquarium, there is no need to feed it exclusively live organisms. Fish meat, shrimp, mollusks, and mussels can be included in the diet. It is also important to provide some plant-based food by offering pieces of green vegetables. Juveniles can be fed bloodworms or earthworms.

Cases of successful Dimidiochromis breeding in artificial environments are known. Females show a preference for laying eggs on hard, flat surfaces, such as flat stones. After laying, the eggs are immediately taken into the female's mouth — this is a protective mechanism characteristic of most cichlids. Throughout the entire incubation period, which lasts from 21 to 28 days, the eggs remain in the female's mouth. During this time, she cannot eat, and if feeding before spawning was irregular or insufficient, the female may release the eggs prematurely. The fertilization process is no less fascinating. On the male's anal fin, there is a characteristic pattern of several bright spots that resemble eggs in shape and color. The female, mistakenly taking these spots for real eggs, tries to collect them; at this moment, the male releases seminal fluid, and fertilization occurs.

A characteristic disease for this and other cichlid species is "Malawi bloat." The main causes of its occurrence lie in suboptimal keeping conditions and an unbalanced diet. Changes in water parameters or the absence of plant additives in the food can provoke this disease. More details on symptoms and treatment methods can be found in the "Diseases of aquarium fish" section.

When choosing a healthy specimen, pay attention to the fish's activity and the cleanliness of its skin. Avoid purchasing individuals with signs of emaciation, sunken bellies, or scale damage. It is important to assess behavior: a healthy fish should show natural curiosity and not have signs of apathy or unnatural swimming. Make sure the fish has no film, ulcers, or signs of fin rot.

• prefer individuals with clear eyes, without cloudiness
• observe the fish's reaction to food in the store to ensure there are no appetite problems
• avoid fish that stay near the water surface or breathe heavily, as this may indicate gill problems or poor water quality in the aquarium