Brochis britskii

Adults of this catfish can reach a length of 8–9 cm. Outwardly, it resembles the Emerald Catfish, its close relative, but significantly surpasses it in size. Brochis britskii also shares similarities with another species, Brochis multiradiatus, due to its elongated dorsal fin, which extends almost to the tail. The fish's coloration is striking, shimmering from orange hues to emerald-green tones depending on the intensity of the lighting. Noticeable barbels are located near the mouth, and the catfish uses them to sift through the substrate in search of food. Sexual dimorphism in this species is weakly expressed, making sex determination quite difficult without specialized knowledge.

This species is endemic to a small section of the Paraguay River (Río Paraguay in Spanish, Rio Paraguai in Portuguese), located in the Brazilian state of Mato Grosso. It can be found in the upper reaches of the river, in the area of numerous backwaters, small tributaries, and lakes.

This peaceful and gregarious species is preferably kept in a group of at least 6–8 individuals. Brochis britskii coexists successfully with many other common aquarium fish. Furthermore, due to its impressive size and natural "armor," it can even live with fairly aggressive species.

For a small group of these catfish, the optimal aquarium size starts from 200 liters. Special attention should be paid to the substrate; it is recommended to use soft sand or fine gravel to minimize the risk of injuring their delicate barbels. It is also advisable to provide several shelters, for example, in the form of snags or other decorative elements. The remaining elements of the aquarium decor do not play a critical role and can be adapted to the aquarist's preferences or the needs of other inhabitants. Acceptable water parameters include a slightly acidic pH level and low carbonate hardness, and a comfortable temperature is in the range of 20–27°C. These fish are sensitive to water quality, so it is necessary to install an efficient filtration system, regularly clean the substrate of organic debris, and weekly replace part of the water (15–20% of the total volume) with fresh water.

The catfish readily accepts all common types of food: dry, frozen, and live. The only important thing is that the food must be sinking. A varied diet contributes to the well-being of the fish and positively affects their appearance.

At the time of preparing this article, no reliable data has been found on the successful breeding of the Giant Emerald Catfish in home aquarium conditions. Fish sold are usually raised on fish farms or, less frequently, caught from natural bodies of water.

The main cause of most diseases in Leaf Fish is unsuitable keeping conditions and poor-quality nutrition. If initial symptoms are observed, it is first necessary to check water parameters and the concentration of dangerous substances such as ammonia, nitrites, and nitrates. If the indicators deviate from the norm, they should be brought back into order, and only then should treatment begin. More detailed information on symptoms and treatment methods can be found in the "Aquarium Fish Diseases" section.

When choosing Corydoras britskii in a store, attention should be paid to the activity and appearance of the individuals. Healthy fish should show interest in searching for food on the bottom, have clean fins without signs of erosion, intact barbels, and smooth scales without spots, sores, or film. Avoid specimens with sunken bellies, signs of emaciation, or unnaturally bloated abdomens.

• check for any damage or redness in the gill and fin areas
• observe their behavior: the fish should be active, not sluggish or constantly lying on their side
• clarify the keeping conditions in the store, as stress from transportation and changes in water parameters can weaken the species' immunity

Since this species is schooling, it is recommended to purchase a group of several individuals at once. It is important to ensure that there are no aggressive neighbors in the aquarium with the fish, as a stressed catfish becomes more vulnerable to diseases.