I had a group many years ago. They are not seen up here, but you should be able to get them (in season) from The Wet Spot in Portland. The true Splashing Tetra, Copella arnoldi, is fascinating, and here an aquarium half filled with water is needed, with emersed plants providing leaves above the water surface. A sort of vivarium, as it should still be covered to keep the air above the water warm and moist.
This fish is closely related to the pencilfishes so they are not "tetras" as such, but in the same Order, characiformes. The following info for those unfamiliar with these fishes.
Truly an unique characin in its method of spawning. The male and female pair will jump from the water and cling to the underside of an overhanging leaf for a few seconds, during which the eggs are deposited and fertilized; the parents release themselves and drop back into the water. This procedure is repeated several times until 150 to 200 eggs have been laid. The male then remains under the leaf, periodically splashing water onto the eggs to prevent them from drying out. The eggs hatch in 2-3 days and drop into the water.
There is some variation in the pattern and colouring among fish from different locales, as illustrated in the two photos. Males are larger, with elongated fins and brighter colouring; in both photos, the male fish is above the female.
To allow for spawning, the tank should have space above the water surface for overhanging plant leaves, either from aquatic plants that grow above the water such as Echinodorus macrophyllus, or house plants allowed to grow over the tank. The tank must still be either covered or the water level must be low enough to prevent the fish from escaping the tank, since they are surface fish and avid jumpers. Floating plants are also recommended to provide a sense of security, along with dim lighting. The mouth is upturned, termed "superior," typical of surface-dwelling fish.
Origin and Habitat: Guyana, French Guyana, Suriname and Brazil. Occurs in slower-moving feeder tributary streams and creeks with overhanging vegetation.
Originally described as Copeina arnoldi by Regan (1912), the species was one of 11 in the genus. In 1956, Dr. George S. Meyers erected the genus Copella for three of the species, but all but two species were subsequently moved into the new genus (Gery, 1977). The Sub-Family Pyrrhulininae now contains two tribes, the Pyrrhulinini containing the genera Copeina (2 species), Copella (9 species) and Pyrrhulina (18 species), and the Nannostomini tribe of the closely-related pencilfishes in the genus Nannostomus. The adipose fin is never present and the mouth is superior in the Pyrrhulinini, whereas the mouth is terminal in the Nannostomini and the adipose fin is sometimes present.