Description
The Emperor Tetra is an ideal species for the mature community aquarium. These beautiful, peaceful, shoaling fish should be housed in a well decorated tank that contains plenty of plants (rooted and floating) and spindly driftwood. Male fish sometimes spar with one another as they vie for the attentions of the females, but no real harm should ensue; the displays are very eye-catching as the colours of the male fish intensify and the elongated fins are spread wide. It is best to try and outnumber males with females wherever possible, which is easiest to achieve in larger groups. This will also have the added benefit of making the fish feel more secure, and will result in a more effective, natural looking shoal. Tankmates could include other species of similar size and temperament e.g. other small peaceable tetras, Corydoras catfish, pencilfish, dwarf cichlids such as Apistogramma or Mikrogeophagus spp., and some of the dwarf Loricariids.
There is one other species in the same genus as the Emperor Tetra, that being the Rainbow Tetra (N. lacortei). These fish are quite similar in appearance, but easy to tell apart as male Rainbow Tetras have bright red irises. A black colour variant of the Emperor Tetra is sometimes offered for sale in the aquatics trade as Black Emperor Tetra. This was once thought to be a third species in the Nematobrycon genus (N. amphiloxus) but is now considered a colour morph and synonym of N. palmeri. Recently a gold form has been produced. Another similar-looking fish, although from a different genus altogether, is the Blue/Purple Emperor Tetra (Inpaichthys kerri). Inpaichthys do not grow quite as large and also possess an adipose fin, which is not present in Nematobrycon.
