Cuming's Barb

Adults of this fish rarely exceed 5 cm. Notably, males, while significantly smaller than females, are distinguished by brighter coloration. For many years two colour forms were assigned to this species — yellow-finned and red-finned — but since 2008 the red-finned one has been treated as a separate species, Pethia reval. In Pethia cumingii the fins are yellow and the body is predominantly silvery. A distinctive feature of their coloration is two dark elongated spots: one located immediately behind the gill cover, and the other closer to the base of the tail.

This species is endemic to south-western Sri Lanka, where it is known only from two river systems, the Bentara and the Gin. Its typical habitats are characterized by moderate current and a sand-gravel substrate. Earlier records from the Kelani and Mahaweli rivers further north are now referred to the closely related Pethia reval. Currently, it has been observed that brightly colored fish are less common in the wild, which may indicate significant changes in the population structure due to active harvesting for the aquarium trade. Negative impacts on their numbers are also caused by the reduction of the island's forests and the pollution of water sources due to human activity.

This species is exclusively peaceful and schooling, which implies keeping them in a group of at least 6–10 individuals. Such a number will not only make the fish less timid but also contribute to the development of brighter colors in their coloration. The latter is especially noticeable in males, who, in the presence of potential rivals, will use the intensity of their coloration as a way to attract the attention of females. Cuming's Barb is well compatible with most fish species of similar temperament and size; however, it is not recommended to keep them with large or aggressive fish.

A school of Cuming's Barbs, consisting of several individuals, will thrive in an aquarium of 60 liters or more. The tank's decor does not have strict requirements, but certain elements can give it a more natural look. For example, using a dark substrate in combination with driftwood and creating areas with dense vegetation contributes to this. Floating plants will also be appropriate. Water parameters should have slightly acidic pH values and low concentrations of dissolved calcium and magnesium salts (low dGH value). More detailed information on pH and dGH values, as well as methods for their regulation, can be found in the section "Water Hydrochemical Composition." The minimum equipment set includes a filtration system, lighting, an aerator, and a heater. In this case, the filter performs two functions: it not only purifies the water but also creates a gentle internal current (not too strong), which your fish will appreciate. Aquarium maintenance involves weekly replacement of 15–20% of the water volume with fresh water of similar parameters. Cleaning the substrate of organic waste is done as needed.

These fish are completely undemanding when it comes to food and readily accept all types of feed: dry, frozen, and live. An important condition is that the food must be of high quality (avoid cheap options) and must contain vegetable components. A varied diet contributes to the manifestation of richer coloration in the fish. It is recommended to feed them 2–3 times a day, giving them as much food as they can eat in 5 minutes. Any uneaten leftovers should be removed from the aquarium.

The closely related Pethia reval looks very similar, so breeders should be selected within a single species to avoid hybridization. This is an ideal approach, which, unfortunately, is rarely followed in amateur aquaristics, leading to constant mixing and a shift in the primary coloration to a more silvery hue. Breeding these fish at home is quite simple; they are capable of spawning in a community tank throughout the year. However, due to the lack of parental instincts and a tendency to eat their own eggs, the survival rate of fry in such conditions will be extremely low. Survival chances increase if the young are promptly caught and transferred, for example, to a three-liter jar, or if spawning is organized in a separate tank. Additional information on stimulating spawning and breeding egg-laying species is available in the section "Breeding Aquarium Fish."

The main cause of all aquarium fish diseases is the mismatch of keeping conditions to the specific needs of the species or a significant deterioration in water quality, nutrition, and other factors. Fish do not get sick without an apparent reason; their health deterioration is almost always caused by external circumstances. Only a few selective species, not found in the wild, may have hereditary diseases, but Cuming's Barb is not among them. If problems arise, first check the water parameters and food quality, and only then proceed with medicinal treatment.

When choosing Cuming's Barbs, prioritize individuals with clean fins free of damage, white film, or ulcers. A healthy fish should be active, mobile, and display typical schooling behavior for the species. Avoid purchasing fish with sunken bellies, signs of emaciation, or atypical behavior, such as lethargic hovering at the surface or bottom of the aquarium. — inspect the scales for spots, hemorrhages, and parasites — check the integrity of the fins, as splitting can indicate infections — ensure there are no signs of stress, such as overly pale coloration or convulsive movements — prefer individuals from aquariums where the water appears clear and clean, without a strong odor.