[JessEmmyRyan]

SPECIES NAME: Arius seemani, or Arius jordani, Hexanematichthys seemani, Tachisurus seemani
COMMON NAME: Shark Catfish, Colombian Shark Catfish
SIZE: Up To 24" (60 cm) in nature, although rarely larger than 15" (38 cm) in captivity
pH: 6.8-8 (7.6), 8-30 dH (16), A 2% addition of salt is necessary. This can be accomplished by adding 15 TSP. of salt/ 10 gallons (20 g of salt/10 L).
Minimum Recommended Tank Size: A 40" (102 cm) or 45-55 gallons (170-209 L) is sufficient for young individuals. Adults need a tank of at least 64" (163 cm) or 100-125 gallons (378-472 L). The tank should be well lighted, maybe in a position to receive morning sun. A strong filter is necessary for a powerful current and a good turn-over rate. Provide many caves and hiding places.
Temperature: 72-81°F (22-27°C), A 2% addition of salt is necessary. This can be accomplished by adding 15 TSP. of salt/ 10 gallons (20 g of salt/10 L).
Diet: Live; fish, crustaceans, insect larvae; tablets. This species prefers food in chunks. Has huge appetite and may attack other tank mates if not fed sufficiently.
Breeding: Unsuccessful in captivity because of the area needed. Spawning has been observed in nature. It takes places in freshwater and brackish estuaries. Up to 100 marble-sized eggs are mouth-brooded by the male. Breeding has not been accomplished in aquaria.
PHYSICAL DESCRIPTION: The body is elongated and silver in color and the belly is white. The fins are black and white-tipped. The head is broad, with a large mouth. The eyes are large and protrude from the head. The Shark Catfish possesses three pairs of barbels; one on the upper jaw and two on the lower. The color contrasts fade with age.
SOCIAL BEHAVIOR: Combine only with larger, sturdy fish who live in brackish water. These fish are capable of swallowing fish up to 67% of their length. Keep in groups of four or more individuals. Adults can be combined with marine species; young can be combined with Anableps, Monodactylus, Scatophagus , Tetraodon , and Toxotes species.
DIFFICULTY OF CARE: Young fish are extremely hardy, but aggressive and require live foods. Adults need to be kept in salt water, and are highly aggressive towards smaller fish.
NOTE: A very active fish. Can only be kept in fresh or brackish water while juveniles. With age more salt must be added to the water. Adults require sea water or brackish water. Some populations of this fish migrate south from California during the colder parts of the year. By rotating its pectoral fin in its socket, adult fish can make a loud, croaking sound. This sound is amplified by the swim bladder.