Characins / Characinae / Cardinal Neon

Cardinal Tetra, Cardinal Neon
Paracheirodon axelrodi

SYN: Cheirodon axelrodi, Hyphessobrycon cardinalis

PD: The body is elongated and laterally compressed. An iridescent blue to green stripe extends across the body from tail to snout. Below the stripe is a bright red band that also extends the whole length of the body. The fins are colorless and the back and belly of the fish is silver in color.
SIZE: To 2.8" (7 cm)
SS: Neon Tetra ( Paracheirodon innesi), False Neon Tetra ( P. simulans)
HAB: Shaded areas in small, slow-moving, clear and blackwater creeks. South America; in the Rio Negro and Orinoco rivers.
S: bottom, middle
TANK: 20" (50 cm) or 10 gallons (38 L) is sufficient, although slightly larger tanks are best. Use a well-planted tank with some floating plants to diffuse the light. Have a good air supply and try to keep waste levels low, as Cardinal Tetras are sensitive to these toxic compounds. The tank should be arranged in dark colors to bring out its beautiful colors.
WATER: pH: 4.5-7 (6.0); 2-8 dH (6); 75-82°F (24-28°C)
FOOD: Flakes; live; insect larvae, Brine Shrimp, Tubifex, Daphnia.
SEX: The males are more slender and may have tiny hooks on anal fin
B: The pair should be selected when about a year in age. Separate the pair and condition them on insect larvae and crustaceans. Use a 20" (50 cm) or 10 gallon (38 L) tank for breeding. Its water properties should be as follows: a pH of 5.5, a water hardness of 0-2 dH, and a temperature around 82°F (28°C). Provide a great deal of fine leafed plants to serve as spawning substrates and use no light. The female will spawn in the evening, laying about 500 eggs which fall to the gravel and into plants. The pair should be removed after spawning. The eggs hatch in 24 hours and the fry are free-swimming five days later. The tiny young are difficult to raise. Start feeding the fry with paramecia. Later the fry can be fed on Brine Shrimp nauplii. Frequent partial water changes should be made.
BP: 8. A challenging fish to breed-this is why most fish available are wild-caught.
SB: A shoaling fish that must be keep in groups of at least six. A good community fish that can be kept with other small fish. The Cardinal Tetra will fall prey to large fish, such as Angels.
SC: Tetras, Corydoras, Apistogramma, Discus, gouramis, Hatchetfish.
R: The neon stripe of the Cardinal Tetra and other characins serves to keep the shoal together where water is dark. The Cardinal uses external light for the source of neon stripe. Iridescent particles in pigment cells of neon stripe capture light and reflect it. Depending on the angle of light, the stripe can change from green to blue. At night, the reflects have no light to reflect and the fish are a brownish gray color, almost transparent. It takes about 15 minutes for the reflectors to start reflecting light again. In nature, the Cardinal is a feeder fish for many fish. They die by the thousands and are very common. In 1993, over 30 million Cardinal Tetras were left unsold in Brazil alone! These fish were caught by fishermen, who receive about $1.50 in U.S. dollars for every thousand Cardinals they capture ( T.F.H. #459, Axelrod 197). In well-maintained tank, individuals have been known to live an excess of 10 years. Since most Cardinal Tetras come from the wild, newly imported fish have trouble acclimating to aquaria. After a danger period of three weeks, when these fish are very susceptible, the fish become hardy.
DC: 3. A hardy and delightful fish recommended for a community tank, that does best under a regime of frequent partial water changes.

By Rhett Butler   Mongabay.com
Project Piaba - Community-based conservation project in the Brazilian Amazon focused on fisheries and rainforest conservation