The Mascara Barb, scientifically known as Dawkinsia assimilis, is a striking and relatively uncommon freshwater fish native to the fast-flowing rivers and streams of the Western Ghats in India. This species is highly valued by aquarists for its elegant appearance, peaceful nature, and active schooling behavior, making it a great addition to well-maintained community aquariums, particularly those designed to replicate riverine environments.

Mascara Barbs are characterized by their elongated, torpedo-shaped bodies and distinctive coloration. Their base color is typically silver or golden with a subtle iridescence, while their most notable feature is the bold black markings around their eyes, resembling "mascara," which gives them their name. They also display a black lateral stripe running along the length of their body, and mature males often develop extended, filament-like fin rays with subtle red or yellow highlights, making them especially striking in a well-lit aquarium.

In captivity, Mascara Barbs thrive in aquariums that closely mimic their natural habitat. A tank setup should include a soft, sandy or fine gravel substrate, as well as plenty of rocks, driftwood, and live plants to provide hiding spots and create a naturalistic environment. They prefer well-oxygenated water with moderate to strong flow, similar to the fast-moving streams they originate from. A high-quality filtration system is essential, along with regular water changes to maintain optimal conditions.

These fish are social and should be kept in groups to promote their well-being and encourage natural schooling behavior. A group setting helps them feel more secure and enhances their dynamic movement patterns. They are peaceful and can coexist with other similarly sized, non-aggressive fish, making them excellent candidates for community tanks with species such as other barbs, danios, rasboras, and peaceful bottom-dwellers like loaches.

Their diet should be varied to ensure they receive all necessary nutrients. Mascara Barbs are omnivorous and will readily accept high-quality flake foods, pellets, and live or frozen foods such as brine shrimp, bloodworms, and daphnia. Including vegetable matter in their diet, such as spirulina flakes or blanched greens, is beneficial for their overall health and coloration.

Breeding Mascara Barbs in captivity can be challenging but rewarding. They are egg scatterers, typically laying their eggs among plants or on smooth surfaces. To encourage breeding, maintaining optimal water conditions with well-oxygenated, slightly cooler water and providing a spacious tank with fine-leaved plants or spawning mops can help. Once the eggs are laid, it is advisable to remove the adults to prevent them from eating the eggs. The eggs hatch within a few days, and the fry can be fed with infusoria or finely crushed flake food until they are large enough to accept standard fare.

Overall, the Mascara Barb is an excellent choice for aquarists looking for a peaceful, active, and visually appealing species. Their elegant appearance, social behavior, and adaptability make them a fantastic addition to well-maintained aquariums, particularly those designed to replicate a flowing river habitat. With proper care, they can thrive and bring a touch of movement and sophistication to any aquatic setup.