阿氏丝鳍脂鲤 · Splash Tetra

Overview

Copella arnoldi is remarkable for spawning above the water. A pair jumps together onto a suitable overhanging surface, and the male subsequently splashes the eggs to keep them moist. This upper-level fish suits a mature planted aquarium with appropriate space above the surface.

Distribution & habitat

In the narrower taxonomic interpretation, the species is associated with Brazil's lower Amazon. Similar populations from coastal Guyana, Suriname, and French Guiana have historically been included, but some treatments recognize them as Copella carsevennensis. The boundary remains disputed.

Habitats include streams and small tributaries, extending into flooded forest at high water. Overhanging vegetation is abundant, and decomposing organic matter often gives the water a pale tea color.

Aquarium setup

For long-term care, allow surface dimensions of at least approximately 90 × 30 cm. Dense planting or a paludarium works well. Floating plants provide shade, while overhanging leaves, roots, or branches are useful for observing reproduction. Much of its time is spent near the top, so leave room for surface activity and spawning.

Dry leaves add cover and support microorganisms that can supplement fry food. Maintain oxygen with gentle surface movement. Introduce fish only once filtration and water chemistry are stable.

Diet & feeding

In nature it eats tiny invertebrates and other zooplankton, particularly at the surface. Suitable-sized prepared foods are accepted, but daily small live or frozen foods should accompany them. Artemia nauplii, small water fleas, and grindal worms are useful choices.

Small crickets and fruit flies are also suitable. Feeding the insects fish flakes or plant material before offering them improves the nutritional contents they carry.

Behaviour & compatibility

Peaceful temperament does not make it suitable for every community. Consider similarly sized characins, small bottom-dwelling catfishes, or diminutive nonpredatory cichlids only where environmental needs match.

Keep a mixed-sex group of at least eight to ten. Other peaceful schooling fishes can improve confidence. Males display strong colors and distinctive behavior while competing for female attention.

Sexual dimorphism

Males become considerably larger, more colorful, and longer-finned. Breeding males may develop a broad dark band extending backward from behind the gill cover.

Breeding

A mature aquarium may yield occasional fry, but a separate setup allows better control. Use air-driven sponge filtration, abundant floating plants, and approximately 10 cm between the water and lid. Emergent leaves are useful, although glass sides or the cover may also be chosen.

The male tests sites with repeated jumps before courting a female. The pair leaps together and grips the chosen surface with the pelvic fins, sometimes remaining for about ten seconds. Around 10–12 eggs are laid per event, with repeated jumps producing roughly 100–200 overall. Remove the female afterward if desired. The male splashes the clutch with his tail about once a minute, pausing in darkness; he may tend several sites and eggs from more than one female.

Hatching usually takes 36–72 hours, after which fry fall into the water and paternal care ends. Separate adults and fry to reduce predation. Start with Paramecium or very fine foods around 5–50 μm, adding Artemia nauplii or microworms when the fry can manage them. Growth is slow.

Notes

Proposed differences from Copella carsevennensis include white centers on some male scales, a breeding band, dark edges on certain fins, and deposition above rather than below water. Taxonomic opinions differ. Neither a splash-tetra trade label nor membership in Copella guarantees this particular aerial spawning behavior.