Notropis chrosomus, or the Rainbow Shiner, is a colorful freshwater species that thrives in cooler water, making it a great addition to subtropical aquariums.
Overview
Notropis chrosomus, commonly known as the Rainbow Shiner, is a vibrant freshwater species native to the rivers and streams of the southeastern United States. Known for their stunning colors, especially during the breeding season, these fish are a popular choice for cooler water aquariums. They reach a size of 5-8 cm and prefer environments with clean, oxygenated water.
Tank Requirements
Rainbow Shiners thrive in well-oxygenated water with temperatures ranging from 15-22°C, making them ideal for subtropical or unheated tanks. They require a minimum tank size of 60 liters with a pH range of 6.5-8.0 and general hardness (GH) between 5-12. The tank should be well-planted with some open swimming spaces, and the water flow should mimic their natural habitat of streams and rivers. Adding rocks and driftwood can create hiding places and replicate a more natural environment for them.
Feeding and Diet
In the wild, Rainbow Shiners feed on small invertebrates, algae, and plant matter. In captivity, they do well on a diet of high-quality flakes, pellets, and live or frozen foods such as daphnia, bloodworms, and brine shrimp. Offering a variety of foods will help maintain their vibrant coloration and health. Feed them twice a day in small amounts to avoid overfeeding.
Care and Maintenance
Notropis chrosomus is relatively hardy but prefers clean, well-maintained water. Weekly water changes of 25-30% are recommended, and ensuring proper filtration and aeration is crucial for their well-being. They are sensitive to sudden temperature and water chemistry fluctuations, so it is important to maintain stable water parameters. A cooler water environment will suit them best, as they do not tolerate tropical temperatures well.
Compatibility
Rainbow Shiners are peaceful, schooling fish that do best in groups of at least 6-8 individuals. They can be kept with other small, non-aggressive species that share similar water requirements. Suitable tank mates include White Cloud Mountain Minnows, smaller danios, and cool-water species such as Corydoras and small loaches. Avoid keeping them with larger or aggressive fish, as they may become stressed or outcompeted for food.
Breeding
Breeding Rainbow Shiners in captivity can be challenging but rewarding. During the breeding season, males display brighter colors, becoming a striking sight in the aquarium. To encourage breeding, maintain water temperatures at the higher end of their range (20-22°C), and provide plenty of hiding spaces, such as plants and rocks, for the females to scatter their eggs. After spawning, remove the adults to prevent them from eating the eggs. The eggs hatch in 3-5 days, and the fry can be fed with infusoria or liquid fry food until they are large enough to eat baby brine shrimp.