Congo Tetras grow to quite a large size for a tetra, and so can live peacefully with large gouramis and such. However, they are still placid enough to keep with smaller fish as well. When mature, their dorsal fin grows very long and arcs back all the way to the base of their tail fin. The tailfin also has a very unique shape. They develop a metallic blue sheen along their bodies with a coppery undertone.
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